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0000038721FRANKLIN CUSTODIAN FUNDS4972018-09-102018-09-102017-09-30false2018-09-10Fund SummaryInvestment GoalCapital appreciation.Fees and Expenses of the FundYou may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $50,000 in Franklin Templeton funds.50000<div><p>These tables describe the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $50,000 in Franklin Templeton funds. More information about these and other discounts is available from your financial professional and under “Your Account” on page 115 in the Fund's Prospectus and under “Buying and Selling Shares” on page 77 of the Fund’s Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in Appendix A - "Intermediary Sales Charge Discounts and Waivers" to the Fund's prospectus.</p><p>Please note that the tables and examples below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions that a shareholder may be required to pay directly to its financial intermediary when buying or selling Class R6 or Advisor Class shares.</p></div>Shareholder Fees (fees paid directly from your investment)~ http://www.proofPlus.com/role/ShareholderFeesS000006754_FranklinCustodianFunds22 column period compact * ~0.000.000.000.000.000.00<div><p>Annual Fund Operating Expenses</p><p>(expenses that you pay each year as a percentage of the value of your investment)</p></div>~ http://www.proofPlus.com/role/OperatingExpensesS000006754_FranklinCustodianFunds22 column period compact * ~0.00460.00460.00460.00460.00460.00250.01000.00500.000.00ExampleThis Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:63682010201596~ http://www.proofPlus.com/role/ExpenseExampleS000006754_FranklinCustodianFunds22 column period compact * ~267519896195411636463213975216629065265207361810If you do not sell your shares:~ http://www.proofPlus.com/role/ExpenseExampleNoRedemptionS000006754_FranklinCustodianFunds22 column period compact * ~1675198961954Portfolio Turnover0.1985<div><p>The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 19.85% of the average value of its portfolio.</p></div>Principal Investment StrategiesUnder normal market conditions, the Fund seeks investments primarily in equity securities of companies that the investment manager believes are leaders in innovation, take advantage of new technologies, have superior management, and benefit from new industry conditions in the dynamically changing global economy.<div><p>Under normal market conditions, the Fund seeks investments primarily in equity securities of companies that the investment manager believes are leaders in innovation, take advantage of new technologies, have superior management, and benefit from new industry conditions in the dynamically changing global economy. The Fund invests predominantly in common stock.</p><p>In pursuing these objectives, the investment manager may invest in companies in any economic sector or of any market capitalization and may invest in companies both inside and outside of the United States. Although the investment manager searches for investments across a large number of sectors, it expects to have significant positions in particular sectors including, for example, technology and health care.</p><p>The investment manager uses fundamental, "bottom-up" research to seek companies meeting its criteria of growth potential, quality and valuation. In seeking sustainable growth characteristics, the investment manager looks for companies it believes can produce sustainable earnings and cash flow growth, evaluating the long-term market opportunity and competitive structure of an industry to target leaders and emerging leaders.</p></div>Principal Risks<div><p>You could lose money by investing in the Fund. Mutual fund shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. government.</p><p>Market</p><p>The market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value of a security or other investment may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.</p><p>Stock prices tend to go up and down more dramatically than those of debt securities. A slower-growth or recessionary economic environment could have an adverse effect on the prices of the various stocks held by the Fund.</p><p>Focus</p><p>The technology sector has historically been volatile due to the rapid pace of product change and development within the sector. Companies in the technology sector may be affected by worldwide technological developments, the success of their products and services (which may be outdated quickly), anticipated products or services that are delayed or cancelled, and investor perception of the company and/or its products or services. The activities of health care companies may be funded or subsidized by federal and state governments and changes in funding may adversely affect the profitability of these companies. Technology and health care companies may also be affected by legislation or changes in government regulation and policies.</p><p>Smaller and Midsize Companies</p><p>Securities issued by smaller and midsize companies may be more volatile in price than those of larger companies, involve substantial risks and should be considered speculative. Such risks may include greater sensitivity to economic conditions, less certain growth prospects, and lack of depth of management and funds for growth and development. They may also have limited product lines or be developing or marketing new products or services for which markets are not yet established and may never become established. In addition, smaller and midsize companies may be particularly affected by interest rate increases, as they may find it more difficult to borrow money to continue or expand operations, or may have difficulty in repaying any loans.</p><p>Foreign Securities</p><p>Investing in foreign securities typically involves more risks than investing in U.S. securities, including risks related to currency exchange rates and policies, country or government specific issues, less favorable trading practices or regulation and greater price volatility. Certain of these risks also may apply to securities of U.S. companies with significant foreign operations.</p><p>Management</p><p>The Fund is subject to management risk because it is an actively managed investment portfolio. The Fund's investment manager applies investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these decisions will produce the desired results.</p><p>Growth Style Investing</p><p>Growth stock prices reflect projections of future earnings or revenues, and can, therefore, fall dramatically if the company fails to meet those projections. Prices of these companies’ securities may be more volatile than other securities, particularly over the short term.</p></div>Performancefranklintempleton.com(800) DIAL BEN/342-5236The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance.Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.<div><p>The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You can obtain updated performance information at franklintempleton.com or by calling (800) DIAL BEN/342-5236.</p><p>The secondary index in the table below show how the Fund's performance compares to other groups of securities.</p><p>Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.</p></div>Class A Annual Total Returns-0.41010.47110.1851-0.02470.15420.39670.07200.08460.01270.3931~ http://www.proofPlus.com/role/AnnualTotalReturnsBarChartS000006754_FranklinCustodianFunds22 column period compact * ~Best Quarter:2012-03-310.1869Worst Quarter:2008-12-31-0.2341<table style="font: 11px sans-serif; background-color:#DDDDDD" border="0" cellspacing="0" cellpadding="5" width="745"><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Best Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q1'12</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">18.69%</td></tr><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Worst Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q4'08</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">-23.41%</td></tr></table><div><p>Average Annual Total Returns<br/>(figures reflect sales charges)</p><p>For the periods ended December 31, 2017</p></div>~ http://www.proofPlus.com/role/AverageAnnualTotalReturnsS000006754_FranklinCustodianFunds22 column period compact * ~Return Before TaxesFranklin DynaTech Fund0.31310.16640.0960Return After Taxes on DistributionsFranklin DynaTech Fund0.30770.15810.0902Return After Taxes on Distributions and Sale of Fund SharesFranklin DynaTech Fund0.18170.13290.07730.37280.17160.09430.38960.17740.09930.39880.39680.18330.10510.30210.17330.10000.21830.15790.0850<div><p>No one index is representative of the Fund's portfolio.</p><p>The figures in the average annual total returns table above reflect the Class A maximum front-end sales charge of 5.75% that was in effect prior to September 10, 2018. Class A shares, however, currently are subject to a maximum front-end sales charge of 5.50% effective on September 10, 2018. If the maximum front-end sales charge of 5.50% was reflected, performance for Class A in the average annual total returns table would be higher.</p><p>Historical performance for Class R and Advisor Class shares prior to their inception is based on the performance of Class A shares. Class R and Advisor Class performance have been adjusted to reflect differences in sales charges and 12b-1 expenses (with respect to Class R only) between classes.</p><p>The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown only for Class A and after-tax returns for other classes will vary.</p></div>Investment GoalCapital appreciation.Fees and Expenses of the FundYou may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $50,000 in Franklin Templeton funds.50000<div><p>These tables describe the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $50,000 in Franklin Templeton funds. More information about these and other discounts is available from your financial professional and under “Your Account” on page 115 in the Fund's Prospectus and under “Buying and Selling Shares” on page 77 of the Fund’s Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in Appendix A - "Intermediary Sales Charge Discounts and Waivers" to the Fund's prospectus.</p><p>Please note that the tables and examples below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions that a shareholder may be required to pay directly to its financial intermediary when buying or selling Class R6 or Advisor Class shares.</p></div>Shareholder Fees (fees paid directly from your investment)~ http://www.proofPlus.com/role/ShareholderFeesS000006755_FranklinCustodianFunds22 column period compact * ~0.000.000.000.000.000.00<div><p>Annual Fund Operating Expenses</p><p>(expenses that you pay each year as a percentage of the value of your investment)</p></div>~ http://www.proofPlus.com/role/OperatingExpensesS000006755_FranklinCustodianFunds22 column period compact * ~0.00450.00450.00450.00450.00450.00250.01000.00500.000.00ExampleThis Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:63481410101574~ http://www.proofPlus.com/role/ExpenseExampleS000006755_FranklinCustodianFunds22 column period compact * ~265513886193311435862113745015927962863201350786If you do not sell your shares:~ http://www.proofPlus.com/role/ExpenseExampleNoRedemptionS000006755_FranklinCustodianFunds22 column period compact * ~1655138861933Portfolio Turnover0.0560<div><p>The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 5.60% of the average value of its portfolio.</p></div>Principal Investment StrategiesUnder normal market conditions, the Fund invests substantially in the equity securities of companies that are leaders in their industries.<div><p>Under normal market conditions, the Fund invests substantially in the equity securities of companies that are leaders in their industries. In selecting securities, the investment manager considers many factors, including historical and potential growth in revenues and earnings, assessment of strength and quality of management, and determination of a company's strategic positioning in its industry.</p><p>Although the Fund normally invests substantially in the equity securities (principally common stocks) of U.S.-based large and medium market capitalization companies, it may invest in companies in new and emerging industries where growth is expected to be above average and may invest up to 25% of its assets in smaller companies.</p><p>The Fund's investment manager is a research driven, fundamental investor, generally pursuing a "buy-and-hold" growth strategy. As a "bottom-up" investor focusing primarily on individual securities, the investment manager chooses companies that it believes are positioned for growth in revenues, earnings or assets. Such advantages as a particular marketing niche, proven technology, sound financial records, strong management, and industry leadership are all factors the investment manager believes point to strong growth potential. Although the investment manager searches for investments across a large number of sectors, from time to time, based on economic conditions, the Fund may have significant positions in particular sectors.</p></div>Principal Risks<div><p>You could lose money by investing in the Fund. Mutual fund shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. government.</p><p>Market</p><p>The market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value of a security or other investment may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.</p><p>Stock prices tend to go up and down more dramatically than those of debt securities. A slower-growth or recessionary economic environment could have an adverse effect on the prices of the various stocks held by the Fund.</p><p>Focus</p><p>To the extent that the Fund focuses on particular countries, regions, industries, sectors or types of investment from time to time, the Fund may be subject to greater risks of adverse developments in such areas of focus than a fund that invests in a wider variety of countries, regions, industries, sectors or investments.</p><p>Growth Style Investing</p><p>Growth stock prices reflect projections of future earnings or revenues, and can, therefore, fall dramatically if the company fails to meet those projections. Prices of these companies’ securities may be more volatile than other securities, particularly over the short term.</p><p>Smaller and Midsize Companies</p><p>Securities issued by smaller and midsize companies may be more volatile in price than those of larger companies, involve substantial risks and should be considered speculative. Such risks may include greater sensitivity to economic conditions, less certain growth prospects, and lack of depth of management and funds for growth and development. They may also have limited product lines or be developing or marketing new products or services for which markets are not yet established and may never become established. In addition, smaller and midsize companies may be particularly affected by interest rate increases, as they may find it more difficult to borrow money to continue or expand operations, or may have difficulty in repaying any loans.</p><p>Management</p><p>The Fund is subject to management risk because it is an actively managed investment portfolio. The Fund's investment manager applies investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these decisions will produce the desired results.</p></div>Performancefranklintempleton.com(800) DIAL BEN/342-5236The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance.Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.<div><p>The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You can obtain updated performance information at franklintempleton.com or by calling (800) DIAL BEN/342-5236.</p><p>Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.</p></div>Class A Annual Total Returns-0.33390.34250.14870.00630.13690.29390.14880.01940.08410.2682~ http://www.proofPlus.com/role/AnnualTotalReturnsBarChartS000006755_FranklinCustodianFunds22 column period compact * ~Best Quarter:2009-09-300.1760Worst Quarter:2008-12-31-0.2030<table style="font: 11px sans-serif; background-color:#DDDDDD" border="0" cellspacing="0" cellpadding="5" width="745"><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Best Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q3'09</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">17.60%</td></tr><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Worst Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q4'08</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">-20.30%</td></tr></table><div><p>Average Annual Total Returns<br/>(figures reflect sales charges)</p><p>For the periods ended December 31, 2017</p></div>~ http://www.proofPlus.com/role/AverageAnnualTotalReturnsS000006755_FranklinCustodianFunds22 column period compact * ~Return Before TaxesFranklin Growth Fund0.19530.14450.0872Return After Taxes on DistributionsFranklin Growth Fund0.18750.13860.0839Return After Taxes on Distributions and Sale of Fund SharesFranklin Growth Fund0.11680.11540.07090.24890.14950.08550.26500.15520.09100.27360.27130.16100.09640.21830.15790.0850<div><p>The figures in the average annual total returns table above reflect the Class A maximum front-end sales charge of 5.75% that was in effect prior to September 10, 2018. Class A shares, however, currently are subject to a maximum front-end sales charge of 5.50% effective on September 10, 2018. If the maximum front-end sales charge of 5.50% was reflected, performance for Class A in the average annual total returns table would be higher.</p><p>The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown only for Class A and after-tax returns for other classes will vary.</p></div>Investment GoalTo maximize income while maintaining prospects for capital appreciation.Fees and Expenses of the FundYou may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds.100000<div><p>These tables describe the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds. More information about these and other discounts is available from your financial professional and under “Your Account” on page 111 in the Fund's Prospectus and under “Buying and Selling Shares” on page 77 of the Fund’s Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in Appendix A – "Intermediary Sales Charge Discounts and Waivers" to the Fund’s prospectus.</p><p>Please note that the tables and examples below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions that a shareholder may be required to pay directly to its financial intermediary when buying or selling Class R6 or Advisor Class shares.</p></div>Shareholder Fees (fees paid directly from your investment)~ http://www.proofPlus.com/role/ShareholderFeesS000006756_FranklinCustodianFunds22 column period compact * ~0.04250.000.000.000.000.000.00<div><p>Annual Fund Operating Expenses</p><p>(expenses that you pay each year as a percentage of the value of your investment)</p></div>~ http://www.proofPlus.com/role/OperatingExpensesS000006756_FranklinCustodianFunds22 column period compact * ~0.00370.00370.00370.00370.00370.00150.00650.00500.000.000.00100.00100.00100.00040.0010ExampleThis Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:4956478131292~ http://www.proofPlus.com/role/ExpenseExampleS000006756_FranklinCustodianFunds22 column period compact * ~486617760117721435862113749931154112014113323352848153268603If you do not sell your shares:~ http://www.proofPlus.com/role/ExpenseExampleNoRedemptionS000006756_FranklinCustodianFunds22 column period compact * ~1143586211374Portfolio Turnover0.3412<div><p>The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 34.12% of the average value of its portfolio.</p></div>Principal Investment Strategies<div><p>Under normal market conditions, the Fund invests in a diversified portfolio of debt and equity securities. The Fund may shift its investments from one asset class to another based on the investment manager's analysis of the best opportunities for the Fund’s portfolio in a given market. The equity securities in which the Fund invests consist primarily of common stocks. Debt securities include all varieties of fixed, floating and variable rate instruments, including secured and unsecured bonds, bonds convertible into common stock, senior floating rate and term loans, mortgage-backed securities and other asset-backed securities, debentures, and shorter term instruments. The Fund seeks income by selecting investments such as corporate, foreign and U.S. Treasury bonds, as well as stocks with dividend yields the investment manager believes are attractive. The Fund may invest up to 100% of its total assets in debt securities that are rated below investment grade (also known as "junk bonds"), including a portion in defaulted securities. The Fund maintains the flexibility to invest in securities of companies from a variety of sectors, but from time to time, based on economic conditions, the Fund may have significant investments in particular sectors. The Fund may also invest up to 25% of its assets in foreign securities, either directly or through depositary receipts.</p><p>The Fund may invest up to 20% of its net assets in equity-linked notes, which are hybrid derivative-type instruments that are specially designed to combine the characteristics of one or more reference securities (usually a single stock, a stock index or a basket of stocks (underlying securities)) and a related equity derivative, such as a put or call option, in a single note form.</p><p>The Fund's investment manager searches for undervalued or out-of-favor securities it believes offer opportunities for income today and significant growth tomorrow. It generally performs independent analysis of the debt securities being considered for the Fund's portfolio, rather than relying principally on the ratings assigned by rating organizations. In analyzing both debt and equity securities, the investment manager considers a variety of factors, including:</p><p>a security's relative value based on such factors as anticipated cash flow, interest or dividend coverage, asset coverage, and earnings prospects;</p><p>the experience and strength of the company's management;</p><p>the company's changing financial condition and market recognition of the change;</p><p>the company's sensitivity to changes in interest rates and business conditions; and</p><p>the company's debt maturity schedules and borrowing requirements.</p><p>When choosing equity investments for the Fund, the investment manager applies a "bottom-up," value oriented, long-term approach, focusing on the market price of a company's securities relative to the investment manager's evaluation of the company's long-term earnings, asset value and cash flow potential. The investment manager also considers a company's price/earnings ratio, profit margins and liquidation value.</p></div>Principal Risks<div><p>You could lose money by investing in the Fund. Mutual fund shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. government.</p><p>Market</p><p>The market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value of a security or other investment may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.</p><p>Stock prices tend to go up and down more dramatically than those of debt securities. A slower-growth or recessionary economic environment could have an adverse effect on the prices of the various stocks held by the Fund.</p><p>High-Yield Debt Securities</p><p>Issuers of lower-rated or "high-yield" debt securities (also known as "junk bonds") are not as strong financially as those issuing higher credit quality debt securities. High-yield debt securities are generally considered predominantly speculative by the applicable rating agencies as their issuers are more likely to encounter financial difficulties and are more vulnerable to changes in the relevant economy, such as a recession or a sustained period of rising interest rates, that could affect their ability to make interest and principal payments when due. The prices of high-yield debt securities generally fluctuate more than those of higher credit quality. High-yield debt securities are generally more illiquid (harder to sell) and harder to value.</p><p>Interest Rate</p><p>When interest rates rise, debt security prices generally fall. The opposite is also generally true: debt security prices rise when interest rates fall. Interest rate changes are influenced by a number of factors, including government policy, monetary policy, inflation expectations, perceptions of risk, and supply of and demand for bonds. In general, securities with longer maturities or durations are more sensitive to interest rate changes.</p><p>Credit</p><p>An issuer of debt securities may fail to make interest payments or repay principal when due, in whole or in part. Changes in an issuer's financial strength or in a security's credit rating may affect a security's value.</p><p>Foreign Securities</p><p>Investing in foreign securities typically involves more risks than investing in U.S. securities, including risks related to currency exchange rates and policies, country or government specific issues, less favorable trading practices or regulation and greater price volatility. Certain of these risks also may apply to securities of U.S. companies with significant foreign operations.</p><p>Income</p><p>Because the Fund can only distribute what it earns, the Fund's distributions to shareholders may decline when prevailing interest rates fall or when the Fund experiences defaults on debt securities it holds.</p><p>Prepayment</p><p>Prepayment risk occurs when a debt security can be repaid in whole or in part prior to the security's maturity and the Fund must reinvest the proceeds it receives, during periods of declining interest rates, in securities that pay a lower rate of interest. Also, if a security has been purchased at a premium, the value of the premium would be lost in the event of prepayment. Prepayments generally increase when interest rates fall.</p><p>Focus</p><p>To the extent that the Fund focuses on particular countries, regions, industries, sectors or types of investment from time to time, the Fund may be subject to greater risks of adverse developments in such areas of focus than a fund that invests in a wider variety of countries, regions, industries, sectors or investments.</p><p>Equity-Linked Notes (ELNs)</p><p>ELNs may not perform as expected and could cause the Fund to realize significant losses including its entire principal investment. Other risks include counterparty risk, liquidity risk and imperfect correlation between ELNs and the underlying securities.</p><p>Management</p><p>The Fund is subject to management risk because it is an actively managed investment portfolio. The Fund's investment manager applies investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these decisions will produce the desired results.</p><p>Value Style Investing</p><p>A value stock may not increase in price as anticipated by the investment manager if other investors fail to recognize the company's value and bid up the price, the markets favor faster-growing companies, or the factors that the investment manager believes will increase the price of the security do not occur or do not have the anticipated effect.</p></div>Performancefranklintempleton.com(800) DIAL BEN/342-5236The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance.Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.<div><p>The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You can obtain updated performance information at franklintempleton.com or by calling (800) DIAL BEN/342-5236.</p><p>The secondary indices in the table below show how the Fund's performance compares to a group of securities that align with a portion of the Fund's portfolio and to the returns of an index of funds with similar investment objectives as the Fund, respectively.</p><p>Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.</p></div>Class A Annual Total Returns-0.30510.35010.12910.02830.13680.14230.0412-0.07810.16290.0841~ http://www.proofPlus.com/role/AnnualTotalReturnsBarChartS000006756_FranklinCustodianFunds22 column period compact * ~Best Quarter:2009-06-300.1879Worst Quarter:2008-09-30-0.1545<table style="font: 11px sans-serif; background-color:#DDDDDD" border="0" cellspacing="0" cellpadding="5" width="745"><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Best Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q2'09</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">18.79%</td></tr><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Worst Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q3'08</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">-15.45%</td></tr></table><div><p>Average Annual Total Returns<br/>(figures reflect sales charges)</p><p>For the periods ended December 31, 2017</p></div>~ http://www.proofPlus.com/role/AverageAnnualTotalReturnsS000006756_FranklinCustodianFunds22 column period compact * ~Return Before TaxesFranklin Income Fund0.03910.05760.0508Return After Taxes on DistributionsFranklin Income Fund0.02000.03780.0296Return After Taxes on Distributions and Sale of Fund SharesFranklin Income Fund0.02520.03690.03110.03910.05760.05080.07220.06170.05020.08180.06330.05180.08670.08620.06800.05710.21830.15790.08500.03540.02100.04000.12750.07290.0495<div><p>No one index is representative of the Fund's portfolio.</p><p>Historical performance for Class A shares in the bar chart and table above prior to their inception is based on the performance of Class A1 shares and has not been adjusted to reflect differences in Rule 12b-1 fees between classes. If Class A shares’ performance was recalculated to reflect Class A shares’ Rule 12b-1 fees, the performance shown would be lower.</p><p>The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown only for Class A and after-tax returns for other classes will vary.</p></div>Investment GoalIncome.Fees and Expenses of the FundYou may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds.100000<div><p>These tables describe the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds. More information about these and other discounts is available from your financial professional and under “Your Account” on page 111 in the Fund's Prospectus and under “Buying and Selling Shares” on page 77 of the Fund’s Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in Appendix A – "Intermediary Sales Charge Discounts and Waivers" to the Fund’s prospectus.</p><p>Please note that the tables and examples below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions that a shareholder may be required to pay directly to its financial intermediary when buying or selling Class R6 or Advisor Class shares.</p></div>Shareholder Fees (fees paid directly from your investment)~ http://www.proofPlus.com/role/ShareholderFeesS000006757_FranklinCustodianFunds22 column period compact * ~0.04250.000.000.000.000.000.00<div><p>Annual Fund Operating Expenses</p><p>(expenses that you pay each year as a percentage of the value of your investment)</p></div>~ http://www.proofPlus.com/role/OperatingExpensesS000006757_FranklinCustodianFunds22 column period compact * ~0.00450.00450.00450.00450.00450.00770.01270.01120.00500.0062ExampleThis Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:5106918871452~ http://www.proofPlus.com/role/ExpenseExampleS000006757_FranklinCustodianFunds22 column period compact * ~5006618351339229403697153411435661713635116028062863199346774If you do not sell your shares:~ http://www.proofPlus.com/role/ExpenseExampleNoRedemptionS000006757_FranklinCustodianFunds22 column period compact * ~1294036971534Portfolio Turnover0.8672<div><p>The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 86.72% of the average value of its portfolio.</p></div>Principal Investment StrategiesUnder normal market conditions, the Fund invests at least 80% of its net assets in U.S. government securities.<div><p>Under normal market conditions, the Fund invests at least 80% of its net assets in U.S. government securities. The Fund presently invests substantially all of its assets in Government National Mortgage Association obligations (Ginnie Maes). Ginnie Maes represent an ownership interest in mortgage loans pooled together for sale to investors to finance purchases of homes. The mortgage loans may have either fixed or adjustable interest rates. As the underlying mortgage loans are paid off, Ginnie Maes provide investors with monthly payments of interest and principal as well as any unscheduled prepayments on the underlying mortgage loans.</p><p>Ginnie Maes carry a guarantee as to the timely repayment of principal and interest that is backed by the full faith and credit of the U.S. government. The full faith and credit guarantee does not apply to the market prices and yields of the Ginnie Maes or to the net asset value or performance of the Fund, which will vary with changes in interest rates and other market conditions.</p></div>Principal Risks<div><p>You could lose money by investing in the Fund. Mutual fund shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. government.</p><p>Interest Rate</p><p>When interest rates rise, debt security prices generally fall. The opposite is also generally true: debt security prices rise when interest rates fall. Interest rate changes are influenced by a number of factors, including government policy, monetary policy, inflation expectations, perceptions of risk, and supply of and demand for bonds. In general, securities with longer maturities or durations are more sensitive to interest rate changes.</p><p>Prepayment</p><p>The Fund may receive unscheduled payments of principal due to voluntary prepayments, refinancing or foreclosure on the underlying mortgage loans. To the Fund this means a loss of anticipated interest. Also, if a security has been purchased at a premium, the value of the premium would be lost in the event of prepayment. Prepayments generally increase when interest rates fall.</p><p>Extension</p><p>The market value of some debt securities (such as certain asset-backed and mortgage-backed securities) will be adversely affected when bond calls or prepayments on underlying mortgages or other assets are less or slower than anticipated, particularly when interest rates rise. When that occurs, the effective maturity date of the Fund’s investment may be extended, resulting in an increase in interest rate sensitivity to that of a longer-term instrument. Such extension may also effectively lock-in a below market interest rate and reduce the value of the debt security.</p><p>Ginnie Maes</p><p>Ginnie Maes differ from conventional corporate debt securities because principal is paid back monthly over the life of the security rather than at maturity. The Fund may receive unscheduled payments of principal due to voluntary prepayments, refinancing or foreclosure on the underlying mortgage loans. Because of prepayments, Ginnie Maes may be less effective than some other types of securities as a means of "locking in" long-term interest rates and may have less potential for capital appreciation during periods of falling interest rates. A reduction in the anticipated rate of principal prepayments, especially during periods of rising interest rates, may increase the effective maturity of Ginnie Maes, making them more susceptible than some other debt securities to a decline in market value when interest rates rise.</p><p>Income</p><p>Because the Fund can only distribute what it earns, the Fund's distributions to shareholders may decline when prevailing interest rates fall or when the Fund experiences defaults on debt securities it holds.</p><p>Credit</p><p>U.S. government investments generally have the least credit risk but are not completely free of credit risk. Any downgrade of securities issued by the U.S. government may result in a downgrade of securities issued by its agencies or instrumentalities, including securities issued by Ginnie Mae. While securities issued by Ginnie Mae are backed by the full faith and credit of the U.S. government, guarantees of principal and interest do not apply to market prices, yields or the Fund’s share price.</p><p>Management</p><p>The Fund is subject to management risk because it is an actively managed investment portfolio. The Fund's investment manager applies investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these decisions will produce the desired results.</p><p>Market</p><p>The market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value of a security or other investment may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.</p></div>Performancefranklintempleton.com(800) DIAL BEN/342-5236The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance.Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.<div><p>The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You can obtain updated performance information at franklintempleton.com or by calling (800) DIAL BEN/342-5236.</p><p>The secondary index in the table below shows how the Fund's performance compares with the returns of an index of funds with similar investment objectives as the Fund.</p><p>Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.</p></div>Class A Annual Total Returns0.06880.04770.06080.06810.0153-0.01680.04310.00940.00670.0075~ http://www.proofPlus.com/role/AnnualTotalReturnsBarChartS000006757_FranklinCustodianFunds22 column period compact * ~Best Quarter:2008-12-310.0386Worst Quarter:2013-06-30-0.0209<table style="font: 11px sans-serif; background-color:#DDDDDD" border="0" cellspacing="0" cellpadding="5" width="745"><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Best Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q4'08</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">3.86%</td></tr><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Worst Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q2'13</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">-2.09%</td></tr></table><div><p>Average Annual Total Returns<br/>(figures reflect sales charges)</p><p>For the periods ended December 31, 2017</p></div>~ http://www.proofPlus.com/role/AverageAnnualTotalReturnsS000006757_FranklinCustodianFunds22 column period compact * ~Return Before TaxesFranklin U.S. Government Securities Fund-0.03600.00110.0262Return After Taxes on DistributionsFranklin U.S. Government Securities Fund-0.0486-0.01300.0115Return After Taxes on Distributions and Sale of Fund SharesFranklin U.S. Government Securities Fund-0.0204-0.00550.0142-0.03600.00110.0262-0.00730.00480.02560.00390.00630.02710.01040.00900.01130.03220.01140.00920.02700.01050.01030.0342<div><p>No one index is representative of the Fund's portfolio.</p><p>Historical performance for Class A shares in the bar chart and table above prior to their inception is based on the performance of Class A1 shares and has not been adjusted to reflect differences in Rule 12b-1 fees between classes. If Class A shares’ performance was recalculated to reflect Class A shares’ Rule 12b-1 fees, the performance shown would be lower.</p><p>The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown only for Class A and after-tax returns for other classes will vary.</p></div>Investment GoalCapital appreciation and current income.Fees and Expenses of the FundYou may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds.100000<div><p>These tables describe the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds. More information about these and other discounts is available from your financial professional and under “Your Account” on page 111 in the Fund's Prospectus and under “Buying and Selling Shares” on page 77 of the Fund’s Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in Appendix A – "Intermediary Sales Charge Discounts and Waivers" to the Fund’s prospectus.</p><p>Please note that the tables and examples below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions that a shareholder may be required to pay directly to its financial intermediary when buying or selling Class R6 or Advisor Class shares.</p></div>Shareholder Fees (fees paid directly from your investment)~ http://www.proofPlus.com/role/ShareholderFeesS000006758_FranklinCustodianFunds22 column period compact * ~0.04250.000.000.000.000.000.00<div><p>Annual Fund Operating Expenses</p><p>(expenses that you pay each year as a percentage of the value of your investment)</p></div>~ http://www.proofPlus.com/role/OperatingExpensesS000006758_FranklinCustodianFunds22 column period compact * ~0.00460.00460.00460.00460.00460.00150.00650.00500.000.00ExampleThis Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:5066798661407~ http://www.proofPlus.com/role/ExpenseExampleS000006758_FranklinCustodianFunds22 column period compact * ~4966488141293225390676148911034359513175015727461659186324726If you do not sell your shares:~ http://www.proofPlus.com/role/ExpenseExampleNoRedemptionS000006758_FranklinCustodianFunds22 column period compact * ~1253906761489Portfolio Turnover0.0089<div><p>The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 0.89% of the average value of its portfolio.</p></div>Principal Investment StrategiesUnder normal market conditions, the Fund invests at least 80% of its net assets in the securities of public utilities companies.<div><p>Under normal market conditions, the Fund invests at least 80% of its net assets in the securities of public utilities companies. These are companies that provide electricity, natural gas, water, and communications services to the public and companies that provide services to public utilities companies. The Fund concentrates (invests more than 25% of its total assets) in companies operating in the utilities industry. The Fund invests primarily in equity securities, which consist mainly of common stocks.</p><p>The Fund searches for the best return opportunities available in the global utilities arena with a specific focus on the U.S. electricity and gas sector. Generally, the Fund seeks to invest in companies producing a high percentage of earnings from their regulated operations.</p></div>Principal Risks<div><p>You could lose money by investing in the Fund. Mutual fund shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. government.</p><p>Utilities Industry</p><p>Utility company equity securities, to the extent they are purchased for their dividend yield, historically have been sensitive to interest rate movements: when interest rates have risen, the stock prices of these companies have tended to fall. In some states, utility companies and their rates are regulated; other states have moved to deregulate such companies thereby causing non-regulated companies’ returns to generally be more volatile and more sensitive to changes in revenue and earnings. Certain utilities companies face risks associated with the operation of nuclear facilities for electric generation, including, among other considerations, litigation, the problems associated with the use of radioactive materials and the effects of natural or man-made disasters. In general, all utility companies may face additional regulation and litigation regarding their power plant operations; increased costs from new or greater regulation of these operations; the need to purchase expensive emissions control equipment or new operations due to regulations; and the availability and cost of fuel, all of which may lower their earnings.</p><p>Market</p><p>The market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value of a security or other investment may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.</p><p>Stock prices tend to go up and down more dramatically than those of debt securities. A slower-growth or recessionary economic environment could have an adverse effect on the prices of the various stocks held by the Fund.</p><p>Concentration</p><p>By focusing on an industry or a group of industries, the Fund carries much greater risks of adverse developments and price movements in such industries than a fund that invests in a wider variety of industries. Because the Fund concentrates in a specific industry or group of industries, there is also the risk that the Fund will perform poorly during a slump in demand for securities of companies in such industries.</p><p>Management</p><p>The Fund is subject to management risk because it is an actively managed investment portfolio. The Fund's investment manager applies investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these decisions will produce the desired results.</p></div>Performancefranklintempleton.com(800) DIAL BEN/342-5236The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance.Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.<div><p>The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You can obtain updated performance information at franklintempleton.com or by calling (800) DIAL BEN/342-5236.</p><p>The secondary index in the table below shows how the Fund's performance compares to a group of securities that reflects the broader equity markets universe.</p><p>Sales charges are not reflected in the bar chart, and if those charges were included, returns would be less than those shown.</p></div>Class A Annual Total Returns-0.25600.13820.06850.19440.05650.13710.2518-0.07380.17770.1056~ http://www.proofPlus.com/role/AnnualTotalReturnsBarChartS000006758_FranklinCustodianFunds22 column period compact * ~Best Quarter:2016-03-310.1475Worst Quarter:2008-09-30-0.1314<table style="font: 11px sans-serif; background-color:#DDDDDD" border="0" cellspacing="0" cellpadding="5" width="745"><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Best Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q1'16</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">14.75%</td></tr><tr><td style="border-bottom: 2px solid #ffffff;" valign="top">Worst Quarter:</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">Q3'08</td><td style="border-bottom: 2px solid #ffffff;" valign="bottom" align="right">-13.14%</td></tr></table><div><p>Average Annual Total Returns<br/>(figures reflect sales charges)</p><p>For the periods ended December 31, 2017</p></div>~ http://www.proofPlus.com/role/AverageAnnualTotalReturnsS000006758_FranklinCustodianFunds22 column period compact * ~Return Before TaxesFranklin Utilities Fund0.05880.10460.0650Return After Taxes on DistributionsFranklin Utilities Fund0.04820.09300.0561Return After Taxes on Distributions and Sale of Fund SharesFranklin Utilities Fund0.04250.08140.05110.05880.10460.06500.09020.10860.06420.10230.11040.06590.10880.10760.11600.07120.12110.12620.06310.21830.15790.0850<div><p>No one index is representative of the Fund's portfolio.</p><p>Historical performance for Class A shares in the bar chart and table above prior to their inception is based on the performance of Class A1 shares and has not been adjusted to reflect differences in Rule 12b-1 fees between classes. If Class A shares’ performance was recalculated to reflect Class A shares’ Rule 12b-1 fees, the performance shown would be lower.</p><p>The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown only for Class A and after-tax returns for other classes will vary.</p></div>The Fund publicly began offering Class A shares (formerly Class M shares) on September 10, 2018.Total annual Fund operating expenses differ from the ratio of expenses to average net assets shown in the Financial Highlights, which reflect the operating expenses of the Fund and do not include acquired fund fees and expenses.Other expenses of the Fund have been restated to exclude non-recurring period expenses and for Class R6 shares, to reflect current fiscal year expenses. If the non-recurring prior period expenses were included in the table above, the amounts stated would have been greater.There is a 0.75% contingent deferred sales charge that applies to investments of $500,000 or more (see "Investments of $500,000 or More – Income, U.S. Government Securities and Utilities Funds" under "Choosing a Share Class") and purchases by certain retirement plans without an initial sales charge on shares sold within 18 months of purchase.There is a 1% contingent deferred sales charge that applies to investments of $1 million or more (see "Investments of $1 Million or More – Dynatech and Growth Funds" under "Choosing a Share Class") and purchases by certain retirement plans without an initial sales charge on shares sold within 18 months of purchase.The Fund publicly began offering Class A shares on September 10, 2018. Other expenses for Class A are based on estimated amounts for the current fiscal year.Class R distribution and service (12b-1) fees have been restated to reflect the current fiscal year's distribution and service (12b-1) fees.The investment manager has contractually agreed in advance to reduce its fee as a result of the Fund's investment in a Franklin Templeton money fund (acquired fund) one year following the date of this prospectus. Contractual fee waiver and/or expense reimbursement agreements may not be changed or terminated during the time period set forth above.Other expenses of the Fund have been restated to exclude non-recurring period expenses and for Class R6 shares, to reflect current fiscal year expenses. If the non-recurring prior period expenses were included in the table above, the amounts stated would have been greater. Consequently, the total annual Fund operating expenses differ from the ratio of expenses to average net assets shown in the Financial Highlights.Since inception May 1, 2013.The investment manager has contractually agreed in advance to reduce its fee as a result of the Fund’s investment in other Franklin Templeton funds (acquired fund) for the next 12-month period. In addition, the transfer agent has contractually agreed to waive or limit its transfer agency fees for Class R6 shares of the Fund so that transfer agency fees for that Class do not exceed 0.01% until January 31, 2019. Contractual fee waiver and/or expense reimbursement agreements may not be changed or terminated during the time periods set forth above.Effective October 5, 2018, Class C shares that have been held for 10 years or more will convert automatically into Class A shares later in the month of October 2018 and will be subject to Class A shares’ lower Rule 12b-1 fees. Thereafter, Class C shares of the Fund will convert automatically to Class A shares of the Fund on a monthly basis in the month of, or the month following, the 10-year anniversary of the Class C shares’ purchase date. Such conversions will be on the basis of the relative net asset values of the two classes, will not be subject to Class A shares’ sales charges and are not expected to be a taxable event for federal income tax purposes. Certain shares that are invested through retirement plans, omnibus accounts or in certain other instances may not automatically convert if the financial intermediary does not have the ability to track purchases to credit individual shareholders’ holding periods. (See “Your Account – Choosing a Shares Class – Sales Charges - Class C – Automatic Conversion of Class C Shares to Class A Shares After 10-Year Holding Period” for more information.)