The four-bucket method, why the tax share leaves first, and what to do when the buckets do not add up.
Last updated: 4 September 2026
The failure mode is always the same. A payout lands, it feels like income, and it gets spent as income. Months later the tax bill arrives for money that is already gone, and it gets paid out of the next payout, which was supposed to fund the next account. From there you are permanently one payout behind.
The fix is not discipline. It is arithmetic performed on the day the money arrives, before the money feels like yours.
Every payout divides into four, and the order matters more than the percentages.
A common starting split is 30% tax, 20% living, 25% new accounts, 25% investing. Those are the defaults Propel ships. They are a starting point, not a recommendation: the tax share should come from your actual calculated rate, and the living share from your actual burn.
The tax figures here are illustrative Every percentage in this guide is an example chosen to show the method. What you actually owe depends on your country, your residency and how your income is classified, and it changes from year to year. Work out your own rate with an accountant who knows your jurisdiction before you rely on any split. This is general information, not tax advice.
The tax share is not a percentage you choose The other three buckets are budgeting decisions. The tax bucket is not. It is whatever your jurisdiction says it is for that particular payout, and if that number is 33.5% then the remaining three buckets divide 66.5%, not 70%. Work out the tax first and let it size itself.
Assume a 5,000 payout, a calculated tax rate of 33.5% for this particular payout, and a monthly burn of 2,000.
| Bucket | Share | Amount | Where it goes |
|---|---|---|---|
| Tax reserve | 33.5% | 1,675 | Separate account, untouched |
| Living costs | 20% | 1,000 | Current account, half a month of burn |
| New accounts | 23% | 1,150 | Evaluation budget |
| Investing | 23.5% | 1,175 | Long-term, or cash reserve |
The 5,000 that felt like a good month is really 3,325 once the tax is out, and 2,325 once the month is covered. That is the number to make decisions on. It is still a good month. It is just a smaller good month than it looked.
In a separate account, at a different institution if you can manage it, with no card attached. This sounds excessive and is not. Money in the account you spend from is spendable money, whatever you have labelled it. Friction is the entire point.
If your tax authority allows advance or quarterly payments, paying as you go is better still. Money you have already handed over cannot be spent twice, and you avoid discovering the shortfall at the deadline.
It usually will not, and the reason is informative. If tax plus living costs already exceeds your payout, that is not a budgeting problem to be smoothed over with a smaller percentage somewhere. It means this payout does not cover your fixed obligations, and the honest response is to reduce the burn or to stop funding new accounts until payouts are larger.
This is why Propel refuses to quietly round a split that does not total 100% and tells you instead. A split that does not add up is money with no instruction, and money with no instruction gets spent.
The tax share should shrink during the year if any of your levies are capped, because your effective rate genuinely falls once a ceiling is crossed. That is a real increase in take-home, not a windfall, and it is a good moment to increase the new-accounts bucket rather than the living one, since your fixed costs have not changed.
The living share should be reviewed whenever your actual burn changes, and it is worth measuring rather than estimating. Most people underestimate their monthly costs by a wide margin, and the gap always comes out of the tax bucket.
Propel Audit is trading analytics and planning software. All calculations, simulations and insights are based on the data you provide and are for educational and informational purposes only. It does not constitute financial, tax, or investment advice.