Double Taxation Relief Calculator

The credit method caps your credit at the home-country tax attributable to your foreign-source income specifically, calculated here as home tax on worldwide income multiplied by the foreign-income share of total income, then scaled by the treaty credit limit percentage. Any foreign tax paid above that cap shows up as Excess Credit (Carryover) rather than reducing this year's bill. Raising the treaty credit limit percentage toward 100% widens the cap and shrinks the excess credit.

With it on, the calculator first computes the average tax rate that would apply to your combined worldwide income, then applies that average rate to your domestic income alone — foreign income leaves the tax base but still pushes up the rate charged on what remains. With it off, domestic income is instead taxed at the flat home rate plus surtax. In this calculator's flat-rate model (no progressive brackets), that average rate always works out equal to the flat effective home rate, so toggling this input currently produces the same result either way — it's collected but doesn't change the output. In a jurisdiction with real progressive brackets, the two methods would diverge.

It runs both methods independently and reports whichever produces the lower Total Tax figure as the Better Method. The credit method tends to win when foreign tax paid is close to or above the home tax rate, since a full or near-full credit largely cancels out the home-country tax bill. The exemption method tends to win when the foreign tax rate is much lower than the home rate, especially with progression turned off.

It's added directly to the Home Country Tax Rate to form the effective home rate that feeds every home-country tax calculation in the tool — the no-relief baseline, the credit method's home tax on worldwide income, and the exemption method's tax on domestic income. Raising it increases the home-country tax component uniformly across all three scenarios shown.

The rate is offered for context and cross-checking, but every calculation here runs on the actual dollar amount you report as Foreign Tax Paid, not on the percentage that produced it. Two filers reporting the same rate can still owe very different foreign tax once deductions, credits, or local exemptions are applied, so anchoring the math to the paid amount avoids assuming a clean rate-times-income relationship that real tax returns rarely have.