Service Class Prospectus | MFS Global Research Portfolio | Service Class

MFS Global Research Portfolio Summary of Key Information

Investment Objective

The fund’s investment objective is to seek capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay when you hold shares of the fund.  If the fees and expenses imposed by the insurance company that issued your variable contracts through which the fund is offered were included, your expenses would be higher.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):

Annual Fund Operating Expenses	Service Class Prospectus MFS Global Research Portfolio Service Class
Management Fee	0.75%
Distribution and/or Service (12b-1) Fees	0.25%
Other Expenses	0.19%
Total Annual Fund Operating Expenses	1.19%

Example

This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. If the fees and expenses imposed by the investment vehicle through which an investment in the fund is made were included, your expenses would be higher.

The example assumes that: you invest $10,000 in the fund for the time periods indicated and you redeem your shares at the end of the time periods; your investment has a 5% return each year; and the fund’s operating expenses remain the same.

Although your actual costs will likely be higher or lower, under these assumptions your costs would be:

Expense Example (USD $)	1 YEAR	3 YEARS	5 YEARS	10 YEARS
Service Class Prospectus MFS Global Research Portfolio Service Class	121	378	654	1,443

Portfolio Turnover

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. These transaction 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 40% of the average value of its portfolio.

Principal Investment Strategies

MFS (Massachusetts Financial Services Company, the fund’s investment adviser) normally invests the fund’s assets primarily in U.S. and foreign equity securities, including emerging market equity securities. Equity securities include common stocks, preferred stocks, securities convertible into stocks, equity interests in real estate investment trusts (REITs), and depositary receipts for such securities.

In selecting investments for the fund, MFS is not constrained to any particular investment style. MFS may invest the fund’s assets in the stocks of companies it believes to have above average earnings growth potential compared to other companies (growth companies), in the stocks of companies it believes are undervalued compared to their perceived worth (value companies), or in a combination of growth and value companies.

While MFS may invest the fund’s assets in companies of any size, MFS generally focuses on companies with large capitalizations.

MFS may invest a large percentage of the fund’s assets in issuers in a single country, a small number of countries, or a particular geographic region.

While MFS may use derivatives for any investment purpose, to the extent MFS uses derivatives, MFS expects to use derivatives primarily to increase or decrease exposure to a particular market, segment of the market, or security. Derivatives include futures, forward contracts, options, structured securities, inverse floating rate instruments, and swaps.

A team of investment research analysts selects investments for the fund. MFS allocates the fund’s assets to analysts by broad market sectors.

MFS uses a bottom-up investment approach to buying and selling investments for the fund. Investments are selected primarily based on fundamental analysis of individual issuers. Quantitative models that systematically evaluate issuers may also be considered.

Principal Risks

As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund. An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The principal risks of investing in the fund are:

Stock Market/Company Risk: Stock markets are volatile and can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, and other conditions, as well as to investor perceptions of these conditions. The price of an equity security can decrease significantly in response to these conditions, and these conditions can affect a single issuer or type of security, issuers within a broad market sector, industry or geographic region, or the market in general.

Foreign and Emerging Markets Risk:  Exposure to foreign markets, especially emerging markets, through issuers or currencies can involve additional risks relating to market, economic, industry, political, regulatory, geopolitical, and other conditions. These factors can make foreign investments, especially those in emerging markets, more volatile and less liquid than U.S. investments. In addition, foreign markets can react differently to these conditions than the U.S. market. Emerging markets can have less developed markets, greater custody and operational risk, less developed legal, regulatory, and accounting systems, and greater political, social, and economic instability than developed markets.

Currency Risk:  The value of foreign currencies relative to the U.S. dollar fluctuates in response to market, economic, industry, political, regulatory, geopolitical, and other conditions, and a decline in the value of a foreign currency versus the U.S. dollar reduces the value in U.S. dollars of investments denominated in that foreign currency.

Geographic Concentration Risk: The fund’s performance could be closely tied to the market, currency, economic, political, regulatory, geopolitical, and other conditions in the countries or regions in which the fund invests and could be more volatile than the performance of more geographically-diversified funds.

Derivatives Risk: Derivatives can be highly volatile and involve risks in addition to the risks of the underlying indicator(s) on which the derivative is based. Gains or losses from derivatives can be substantially greater than the derivatives’ original cost.  Derivatives can involve leverage.

Leveraging Risk: Leverage involves investment exposure in an amount exceeding the initial investment. Leverage can cause increased volatility by magnifying gains or losses.

Investment Selection Risk:  MFS’ investment analysis and its selection of investments may not produce the intended results and/or can lead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperforming the markets in which the fund invests.

Counterparty and Third Party Risk: Transactions involving a counterparty or third party other than the issuer of the instrument are subject to the credit risk of the counterparty or third party, and to the counterparty’s or third party’s ability to perform in accordance with the terms of the transaction.

Liquidity Risk: It may not be possible to sell certain investments, types of investments, and/or segments of the market at any particular time or at an acceptable price.

Performance Information

The bar chart and performance table below are intended to provide some indication of the risks of investing in the fund by showing changes in the fund’s performance over time and how the fund’s performance over time compares with that of a broad measure of market performance.

Performance prior to October 6, 2008, reflects time periods when MFS primarily invested the fund’s assets in U.S. equity securities.  Beginning October 6, 2008, MFS primarily invests the fund’s assets in U.S. and foreign equity securities, including emerging market equity securities. The fund’s past performance does not necessarily indicate how the fund will perform in the future. Updated performance is available at mfs.com or by calling 1-877-411-3325. If the fees and expenses imposed by the investment vehicle through which an investment in the fund is made were included, they would reduce the returns shown.

Service Class Bar Chart.

The total return for the three-month period ended March 31, 2013 was 6.22%.During the period(s) shown in the bar chart, the highest quarterly return was 19.46% (for the calendar quarter ended September 30, 2009) and the lowest quarterly return was (23.02)% (for the calendar quarter ended December 31, 2008).

Performance Table.

Average Annual Total Returns (for the Periods Ended December 31, 2012)

Average Annual Returns Service Class Prospectus MFS Global Research Portfolio	Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Service Class	Service Class Shares	16.57%	0.41%	7.06%
Service Class MSCI All Country World Index (gross div)	Index Comparison (Reflects no deduction for fees, expenses or taxes) MSCI All Country World Index (gross div)	16.80%	(0.61%)	8.66%