Tax Equalization

Tax equalization is an assignment compensation policy that keeps an expatriate's tax burden equal to what they would have paid at home. The employee bears a "hypothetical tax" on their pay. The company pays the real home and host country taxes.

Employers use it so a move to a high-tax country does not cut take-home pay and a move to a low-tax country does not create a windfall. Mercer describes the goal as leaving the assignee no better or worse off because of the assignment.

How Does Tax Equalization Work?

The employer deducts the hypothetical tax from the employee's base salary. The company keeps that money instead of sending it to a tax authority, and uses it toward the employee's real tax bills.

The company then pays the actual taxes in both countries. If taxes on assignment run higher than the hypothetical tax, the employer covers the difference. If they run lower, the company keeps the savings.

These payments are income too. The IRS lists amounts paid under a tax equalization plan among employer-provided amounts that count as taxable foreign earned income, so payroll has to report them.

How Is the Hypothetical Tax Calculated?

The hypothetical tax estimates what the employee would owe at home on their salary. It is simpler to set than each person's real liability. Common methods include:

• Deductions taken by the average home-country counterpart.
• A fixed percentage of salary, based on studies of home-country peers.
• An average of the employee's actual deductions over several years before the assignment.

For illustration, say the hypothetical tax is $30,000 and actual taxes total $45,000. The company pays the $15,000 gap. At $25,000, the company keeps the $5,000 difference.

How Does Tax Equalization Compare With Tax Protection and Laissez-Faire?

Mercer groups the main options into four approaches. This table summarizes how they split the cost and risk.

Mercer also notes that protection can raise equity concerns with colleagues elsewhere.

Who Benefits From Tax Equalization?

Employees get predictable net pay without guessing how two tax systems will treat their salary. A high-tax posting becomes easier to accept.

Employers get consistent treatment across destinations, so tax rates do not decide who is willing to go. The trade-off is that the company carries the risk.

What Are the Risks of Tax Equalization?

The policy shifts uncertainty from the employee to the employer. Three risks deserve a line in the budget:

• Cost. The company pays every dollar above the hypothetical tax, and that payment is itself taxable income.
• Tax return dependency. The final settlement waits for returns in both countries. U.S. citizens abroad still owe tax on worldwide income, according to the IRS, so late filings delay the true-up.
• State tax. California, for example, taxes residents on all income, including people domiciled there but abroad for a temporary purpose. Decide whether the hypothetical tax includes state tax and who pays an assessment.

Model all three before approving an assignment.

How Should HR Coordinate Tax Equalization?

Shadow Payroll, covered in a separate entry, handles the reporting side. Align both with global payroll compliance requirements so withholding matches what the tax provider calculates.

Check federal income tax withholding and Social Security tax setups, and confirm the employee's tax residency status. Review broader HR compliance duties before each assignment.

HR Cloud keeps employee records in one place and connects them to payroll through its payroll integrations.

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Frequently Asked Questions

Q: Does tax equalization cover personal income like investments?

A: That is a policy choice. Policies commonly cover salary and bonus, and HR decides whether personal income is included.

Q: Is tax equalization legally required?

A: No. It is an employer policy, not a legal requirement. The employee stays responsible to each tax authority.

Q: Does the company's support continue after the assignment ends?

A: Returns for assignment years are filed afterward, so state in writing how long support continues.

Q: Who prepares the employee's tax returns?

A: Often the company's tax provider, since the foreign earned income exclusion and foreign tax credit are claimed on the U.S. return.

Q: Do policies cover social security contributions?

A: Check the wording. Policies often list covered taxes, and a totalization agreement can prevent paying into two systems.

Q: How does a home state with no income tax change the math?

A: The hypothetical state tax is zero, so the company absorbs more of the host-country bill.