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The short answer
Zero-based budgeting means assigning every naira of your take-home pay to a line before the month begins, so income minus all the lines equals zero. Irregular costs such as school fees and rent become monthly sinking-fund lines, and family support (black tax) gets a fixed monthly allowance; in the ₦420,000 example below, ₦40,000 goes to family and ₦150,000 to rent and fees pots.
Most budgets ask what you spent. A zero-based budget asks, before the month starts, what each naira is for. Spending, saving, family support and future bills all get a line, and the lines add up exactly to your income. "Zero" does not mean you spend everything; savings is a line too. It means nothing is left unassigned to drift away.
How it works
- Start with what you will actually receive this month: salary after PAYE and pension, plus any reliable side income.
- List every fixed cost: transport, power, data, rent instalment, loan repayment.
- Add sinking-fund lines for costs that come yearly or termly.
- Add a fixed line for family support and giving.
- Add savings.
- Give what remains to variable spending: food, outings, personal items.
- Adjust until income minus all lines is exactly ₦0.
Your take-home figure depends on tax. Under the Nigeria Tax Act 2025 bands summarised by PaySpace, the first ₦800,000 of annual taxable income is taxed at 0%, the next ₦2,200,000 at 15% and the next ₦9,000,000 at 18%. Use the net figure on your payslip, not your gross salary.
Worked example: ₦420,000 take-home
| Line | Amount | Type |
|---|---|---|
| Rent pot (yearly rent saved monthly) | ₦100,000 | Sinking fund |
| School fees pot | ₦50,000 | Sinking fund |
| Food and groceries | ₦90,000 | Variable |
| Transport | ₦45,000 | Fixed |
| Electricity | ₦20,000 | Fixed |
| Data and airtime | ₦12,000 | Fixed |
| Family support (black tax) | ₦40,000 | Fixed allowance |
| Emergency fund | ₦30,000 | Savings |
| Giving (church, mosque, contributions) | ₦15,000 | Fixed |
| Personal and fun | ₦18,000 | Variable |
| Total assigned | ₦420,000 | |
| Income minus lines | ₦0 |
Check: 100,000 + 50,000 + 90,000 + 45,000 + 20,000 + 12,000 + 40,000 + 30,000 + 15,000 + 18,000 = ₦420,000. Every naira has a job.
Handling irregular lines
School fees and rent
Divide the yearly or termly cost by the months until it is due and make that a monthly line. A ₦600,000 school bill across three terms is ₦50,000 a month over 12 months. Keep these pots apart from spending money; if they sit in the main account, the zero-based plan collapses. Our guide to sinking funds in naira covers catching up when you start late.
Black tax
Support for parents, siblings and the extended family is a real cost, and pretending otherwise is why many budgets fail. Give it a fixed monthly allowance you can sustain, tell the family roughly what that allowance is, and pay requests from it. When a request is bigger than the allowance, you have a clear question to answer: which other line gives way this month? Our piece on black tax goes further on setting limits kindly.
Unexpected costs
A zero-based budget still needs an emergency line. When something surprising happens, pay it from the emergency fund, then rebuild the fund in the next months' budgets rather than raiding the rent pot.
Zero-based or 50/30/20?
The 50/30/20 rule splits take-home pay into needs, wants and savings by fixed percentages. It is quick, but in Nigeria needs often take far more than half, especially for renters in Lagos or Abuja. A zero-based budget starts from your real costs instead, so it fits whatever your mix is. Many people use both: 50/30/20 as a rough check on whether savings are big enough, and zero-based as the actual plan. Our look at the 50/30/20 rule in Nigeria explains the gap.
The cost of zero-based budgeting is time: about half an hour at the start of each month. The pay-off is that you decide in advance, calmly, instead of deciding at the till.
Months that differ
Zero-based budgets are rebuilt every month, which is their strength. In December you might move ₦30,000 from personal spending to a travel line; in the month the landlord is paid, the rent pot drops to zero and starts again. If your income is irregular, budget from the lowest month you can expect and assign anything extra when it arrives, as in our guide to budgeting on irregular income.
What to check first
- Is your take-home figure the amount that actually lands, not the offer letter?
- Have you listed every yearly or termly bill, including vehicle papers, festive travel and dues?
- Is the family support line a number you can keep paying for twelve months?
- Is there an emergency line, however small?
Steps
- Write your take-home pay at the top.
- List lines in order: fixed, sinking funds, family, savings, variable.
- Adjust until the difference is ₦0.
- Move pot money out on payday.
- Review at month end and rebuild next month.
Transfers between pots cost money if they cross institutions: from January 2026 the sender pays ₦50 stamp duty on electronic transfers of ₦10,000 or more, though transfers between your own accounts at the same institution are exempt, per Kuda's help centre.
Where Pryme fits
With a Pryme Personal Account you can hold each sinking fund in its own naira Savings Box inside the same account, and pay electricity and data bills from the main balance. The Personal Assistant can prepare the payday moves for your approval.
Questions people ask
What is zero-based budgeting in simple terms?
Giving every naira of your monthly income a job before the month starts, so income minus all budget lines equals zero. Savings counts as a job.
Does zero-based budgeting mean I spend all my money?
No. Savings and sinking funds are lines in the budget; zero means nothing is left unassigned.
How do I budget for black tax?
Give family support a fixed monthly allowance you can sustain and pay requests from it. If a request exceeds it, decide which other line gives way.
Is zero-based budgeting good for irregular income?
Yes, if you budget from your lowest expected month and assign extra income when it arrives.
Sources
- PaySpace: Nigeria tax reform 2026 – PIT bands and rent relief (19 Nov 2025) · accessed Oct 2026
- Kuda Help: An important update about stamp duty (modified 5 Jan 2026) · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.