Defined Contribution Plans — Waste Management sponsors a 401(k) retirement savings plan that covers employees, except those working subject to collective bargaining agreements that do not provide for coverage under the plan. U.S. employees who are not subject to such collective bargaining agreements are generally eligible to participate in the plan following a 90-day waiting period after hire and may contribute as much as 50% of their eligible annual compensation and 80% of their annual incentive plan bonus, subject to annual contribution limitations established by the IRS. Under the retirement savings plan, for non-union employees, we match 100% of employee contributions on the first 3% of their eligible annual compensation and 50% of employee contributions on the next 3% of their eligible annual compensation, resulting in a maximum match of 4.5% of eligible annual compensation. Non-union employees hired on or after January 1, 2018 are automatically enrolled in the plan at a 3% contribution rate upon eligibility. Both employee and Company contributions are in cash and vest immediately. Certain U.S. employees who are subject to collective bargaining agreements may participate in the 401(k) retirement savings plan under terms specified in their collective bargaining agreement. Certain employees outside the U.S., including those in Canada, participate in defined contribution plans maintained by the Company in compliance with laws of the appropriate jurisdiction. Charges to operating and selling, general and administrative expenses for our defined contribution plans totaled $88 million, $80 million and $70 million for the years ended December 31, 2019, 2018 and 2017, respectively.

Defined Benefit Plans (other than multiemployer defined benefit pension plans discussed below) — WM Holdings sponsors a defined benefit plan for certain employees who are subject to collective bargaining agreements that provide for participation in this plan. Further, certain of our Canadian subsidiaries sponsor defined benefit plans that are frozen to new participants. As of December 31, 2019, the combined benefit obligation of these pension plans was $141 million supported by $136 million of combined plan assets, resulting in an aggregate unfunded benefit obligation for these plans of $5 million. As of December 31, 2018, the combined benefit obligation of these pension plans was $120 million supported by $117 million of combined plan assets, resulting in an aggregate unfunded benefit obligation for these plans of $3 million.

In addition, WM Holdings and certain of its subsidiaries provided post-retirement health care and other benefits to eligible retirees. In conjunction with our acquisition of WM Holdings in July 1998, we limited participation in these plans to participating retirees as of December 31, 1998. The unfunded benefit obligation for these plans was $14 million and $18 million as of December 31, 2019 and 2018, respectively.

Our accrued benefit liabilities for our defined benefit pension and other post-retirement plans were $19 million and $21 million as of December 31, 2019 and 2018, respectively, and are included as components of accrued liabilities and long-term other liabilities in our Consolidated Balance Sheets.

Multiemployer Defined Benefit Pension Plans — We are a participating employer in a number of trustee-managed multiemployer defined benefit pension plans (“Multiemployer Pension Plans”) for employees who are covered by collective bargaining agreements. The risks of participating in these Multiemployer Pension Plans are different from single-employer plans in that (i) assets contributed to the Multiemployer Pension Plan by one employer may be used to provide benefits to employees or former employees of other participating employers; (ii) if a participating employer stops contributing to the plan, the unfunded obligations of the plan may be required to be assumed by the remaining participating employers and (iii) if we choose to stop participating in any of our Multiemployer Pension Plans, we may be required to

pay those plans a withdrawal amount based on the underfunded status of the plan. The following table outlines our participation in Multiemployer Pension Plans considered to be individually significant (dollars in millions):

(a)

The most recent Pension Protection Act zone status available in 2019 and 2018 is for the plan’s year-end as of December 31, 2018 and 2017, respectively. The zone status is based on information that we received from the plan and is certified by the plan’s actuary. As defined in the Pension Protection Act of 2006, among other factors, plans reported as critical are generally less than 65% funded and plans reported as endangered are generally less than 80% funded. Under the Multiemployer Pension Reform Act of 2014, a plan is generally in critical and declining status if it (i) is certified to be in critical status pursuant to the Pension Protection Act of 2006 and (ii) is projected to be insolvent within the next 15 years or, in certain circumstances, 20 years.

As of the date the financial statements were issued, Forms 5500 were not available for the plan years ended in 2019.

(b)	The “FIP/RP Status” column indicates plans for which a Funding Improvement Plan (“FIP”) or a Rehabilitation Plan (“RP”) has been implemented.

(c)

A Multiemployer Pension Plan that has been certified as endangered, seriously endangered or critical may begin to levy a statutory surcharge on contribution rates. Once authorized, the surcharge is at the rate of 5% for the first 12 months and 10% for any periods thereafter. Contributing employers, however, may eliminate the surcharge by entering into a collective bargaining agreement that meets the requirements of the applicable FIP or RP.

(d)	Of the Multiemployer Pension Plans considered to be individually significant, the Company was listed in the Form 5500 of the Suburban Teamsters of Northern Illinois Pension Plan as providing more than 5% of the total contributions for plan years ending December 31, 2018 and 2017.

(e)	Total contributions to Multiemployer Pension Plans excludes contributions related to withdrawal liabilities discussed below.

Our portion of the projected benefit obligation, plan assets and unfunded liability for the Multiemployer Pension Plans is not material to our financial position. However, the failure of participating employers to remain solvent could affect our portion of the plans’ unfunded liability. Specific benefit levels provided by union pension plans are not negotiated with or known by the employer contributors.

In connection with our ongoing renegotiations of various collective bargaining agreements, we may discuss and negotiate for the complete or partial withdrawal from one or more of these pension plans. Further, business events, such as the discontinuation or nonrenewal of a customer contract, the decertification of a union, or relocation, reduction or discontinuance of certain operations, which result in the decline of Company contributions to a Multiemployer Pension Plan could trigger a partial or complete withdrawal. In the event of a withdrawal, we may incur expenses associated with our obligations for unfunded vested benefits at the time of the withdrawal. In 2019, 2018 and 2017, we recognized charges

of less than $1 million, $3 million and $12 million, respectively, to operating expenses for the withdrawal from certain underfunded Multiemployer Pension Plans. Refer to Note 11 for additional information related to our obligations to Multiemployer Pension Plans for which we have withdrawn or partially withdrawn.

Multiemployer Plan Benefits Other Than Pensions — During the years ended December 31, 2019, 2018 and 2017, the Company made contributions of $45 million, $43 million and $42 million, respectively, to multiemployer health and welfare plans that also provide other post-retirement employee benefits. Funding of benefit payments for plan participants are made at negotiated rates in the respective collective bargaining agreements as costs are incurred.