Canada–U.S. Totalization Agreement Explained

The Canada–U.S. Totalization Agreement decides which country's social security system covers a worker employed or self-employed across the border — so they pay into one, not both — and lets workers combine their credits from both countries to qualify for benefits. An employee sent temporarily (up to five years) stays in the home country's system with a certificate of coverage.

On this page

1. Coverage rules
2. The certificate of coverage
3. Combined benefits
4. Benefit taxation
5. Frequently asked questions
6. Related guides
7. Official sources
8. Next step

Coverage rules

Quebec has its own understanding with the United States for the Quebec Pension Plan (the Quebec cross-border guide).

The certificate of coverage

For a Canadian employee sent to the United States: the CRA issues the certificate on Form CPT56 for CPP (Retraite Québec issues Form Q-111-3 for QPP), and the U.S. employer or the employee keeps it as proof that no FICA is owed on the U.S. wages. For a U.S. employee sent to Canada: the Social Security Administration issues it, exempting the employee from CPP or QPP contributions. Without the certificate, both systems can apply.

Combined benefits

A worker with too few credits in one country to qualify for its benefit can count periods of coverage in the other — each country then pays a partial benefit based on the credits earned in it. The United States totalizes only for a worker with at least six quarters of U.S. coverage and pays a pro-rated share of a full benefit; Canada counts U.S. periods toward the residence minimums for Old Age Security and the contribution minimums for CPP disability and survivor benefits. The Windfall Elimination Provision — which could cut a U.S. benefit for someone also receiving CPP, unless the U.S. benefit was itself a totalization benefit — and the Government Pension Offset (which applied to U.S. government pensions) were repealed by the Social Security Fairness Act, signed January 5, 2025, for benefits payable for January 2024 onward, with retroactive payments.

Benefit taxation

Under the tax treaty, U.S. Social Security paid to a Canadian resident is taxed only in Canada, with 15 percent of it exempt, and Canadian CPP/QPP and Old Age Security paid to a U.S. resident is taxed only in the United States, as if it were U.S. Social Security.

Frequently asked questions

Official sources

The Social Security Administration states: “First, they eliminate dual Social Security taxation, the situation that occurs when a worker from one country works in another country and is required to pay Social Security taxes to both countries on the same earnings. Second, the agreements help fill gaps in benefit protection for workers who have divided their careers between the United States and another country.” — Social Security Administration, U.S. International Social Security Agreements, https://www.ssa.gov/international/agreements_overview.html

IRS Publication 597 states: “This publication provides information on the income tax treaty between the United States and Canada. It discusses a number of treaty provisions that most often apply to U.S. citizens or residents who may be liable for Canadian tax.” — Internal Revenue Service, Publication 597 (10/2015), Information on the United States–Canada Income Tax Treaty, https://www.irs.gov/publications/p597

Next step

Fairlight Accounting is a cross-border accounting and tax practice with a U.S. Tax Desk and a Canadian Tax Desk. Our U.S. Tax Desk and Canadian Tax Desk handle social security coverage planning for cross-border workers — certificates of coverage, detached worker assignments, self-employed coverage, combined benefit analysis, and benefit taxation under the treaty. See pricing or book a call.