One of the most-asked questions at year end: how should my bonus be taxed to cost the least? Separate lump-sum treatment versus combining it with your regular income can differ by hundreds or thousands in tax. In jurisdictions that offer the choice (for example China's annual one-time bonus policy, extended to end-2027), you can pick either — and it pays to actually compute both. Here's how to do it properly.
The Two Methods and How They Differ
Your year-end bonus (annual one-time bonus) can typically be taxed either way:
- Separate lump-sum method: divide the bonus by 12 to get a monthly-equivalent figure, look up the monthly tax bracket, then apply that rate to the entire bonus minus the relevant deduction
- Combined with annual income: add the bonus to your full-year salary and other income, then tax the total under the annual comprehensive income schedule
The methods aren't in conflict — you can compute both and file under whichever gives the lower tax. Use the salary tax calculator, enter your monthly salary and bonus, and see the difference between the two methods side by side.
How the Separate Method Works (with a Sample Bracket Table)
Steps for the lump-sum method:
- Divide the total bonus by 12 → monthly-equivalent taxable amount
- Find the tax rate and deduction in the monthly bracket table
- Tax due = bonus total × rate − deduction
| Monthly-equivalent amount | Rate | Quick deduction |
|---|---|---|
| Up to $400 | 3% | 0 |
| $400–$1,600 | 10% | $28 |
| $1,600–$3,300 | 20% | $188 |
| $3,300–$4,700 | 25% | $355 |
| $4,700–$7,300 | 30% | $588 |
| $7,300–$10,700 | 35% | $955 |
| Over $10,700 | 45% | $2,021 |
Example: a $4,800 bonus ÷ 12 = $400, falling in the 3% bracket. Tax = 4,800 × 3% − 0 = $144.
The Cliff-Edge Trap: One Extra Dollar Can Cost Hundreds
The separate method has rate boundaries, and a bonus landing exactly on one produces the infamous "one extra dollar, hundreds more in tax" effect:
| Bonus amount | Rate applied | Tax due |
|---|---|---|
| $4,800 | 3% | $144 |
| $4,801 | 10% | $452.10 (one extra dollar → ~$308 more tax) |
| $19,200 | 10% | $1,892 |
| $19,201 | 20% | $3,652.20 (one extra dollar → ~$1,760 more tax) |
So before a bonus is paid, avoid landing on the boundary amounts (e.g., 4,800, 19,200, 40,000, 56,000, 88,000, 128,000 in the example currency). Use the percentage calculator to test which bracket a proposed bonus falls into, and if it's at the edge, consider splitting the excess into the next year or restructuring.
When Does Combining with Income Win?
There's no universal "better" method — it depends on your annual income structure:
- Low annual taxable income (below the first bracket after deductions): combining often wins, because you have unused low-bracket capacity
- High annual income already in top brackets: separate treatment usually wins, letting you "park" the bonus in a lower bracket
- Unused deductions and credits: combining lets the bonus consume them first
If your salary plus bonus keeps overall taxable income inside the first bracket, combining may mean paying just 3% on everything. Otherwise, separate treatment can be cheaper. Don't guess — run both with the tax calculator.
Practical Tips for Bonus Season
- Compute both routes: tax the bonus separately and combined, and file under whichever is lower
- Avoid the cliff edges: if the amount sits on a bracket boundary, negotiate with your employer to adjust (e.g., shift the excess to next year)
- Use up deductions: have you maxed out every deduction and credit? It changes whether combining is worth it
- Keep the paperwork: whichever method you elect, keep the calculation for your annual reconciliation
Before bonus season, run both methods through the salary tax calculator and the tax calculator, pick the cheaper election, and keep hundreds in your own pocket.