How much of a pay rise you actually keep.
Net monthly gain
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Gross gain
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Retention rate
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New net
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The gap between the offer letter and your bank balance
A KES 20,000 raise does not put KES 20,000 in your account. Every extra shilling of gross pay passes through the same set of deductions that trimmed your original salary, so the rise arrives smaller than the headline. This calculator computes your take-home before and after the increase and reports the part that actually survives, which it calls the net gain, alongside the retention rate, the share of the gross rise you keep. Going from a number on an offer letter to the number that changes your life is the whole point.
The deductions doing the trimming are Kenya's standard payroll quartet: PAYE, the income tax on a progressive scale; SHIF, the health contribution that replaced NHIF; NSSF, the pension contribution; and the Affordable Housing Levy. The tool runs your old and new gross through the full stack and subtracts one net from the other. The structure of these deductions is stable even as the specific rates move with each Finance Act, which is why the mechanism is worth understanding even when you should confirm the exact figures with the Kenya Revenue Authority.
Why a raise is taxed harder than your base pay
Retention falls as you earn more, and the reason is the progressive PAYE scale. Your first slice of income is taxed gently, but a raise stacks on top of everything you already earn, so it is taxed at your highest, or marginal, rate. The rates this calculator applies climb to 30 percent on income in the broad middle band and higher still at the top, meaning a well-paid worker can lose roughly a third of a raise to PAYE alone before SHIF and the Housing Levy take their cut. That is the structural reason retention for higher earners typically settles somewhere in the mid sixties to low seventies as a percentage, and confirming the current bands with the KRA is wise because they have been revised before.
A raise from KES 100,000 to KES 120,000, line by line
Consider someone moving from KES 100,000 to KES 120,000 a month gross, a KES 20,000 raise. There is a quietly important detail at this income: NSSF is close to its ceiling, contributing KES 6,000 at the lower salary and the KES 6,480 maximum at the higher one, so it takes only KES 480 from the raise. Almost the whole wedge on the extra KES 20,000 is PAYE, SHIF, and the Housing Levy. Using the rates this calculator applies:
| Figure | At 100,000 | At 120,000 |
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Net pay rises from KES 70,442 to KES 83,511, a net gain of KES 13,069 from a KES 20,000 raise. That is a retention rate of about 65 percent: you keep roughly two thirds, and the missing third is overwhelmingly the extra PAYE. The live chart in the results panel above contrasts the gross rise with the slice that reaches you.
Reading the result without being discouraged
Keeping two thirds of a raise is normal and still very much worth having, so do not let the retention rate put you off negotiating. The number is most useful in two ways. First, it lets you translate a salary offer into a real change in spending power before you accept, which is far more honest than comparing gross figures. Second, it reframes non-cash benefits: because additional gross is taxed at your marginal rate, perks that are tax-free or lightly taxed, such as a qualifying pension contribution or certain exempt allowances, can be worth more than the same value handed over as salary.
A common mistake is forgetting that a raise can change more than tax. Crossing into a higher pay bracket can affect things the tool does not model, like benefit eligibility or how a future bonus is taxed, and very large jumps push you into the higher PAYE bands where retention falls further. The calculator also assumes a plain salary with the standard deductions; if you make voluntary pension contributions or claim insurance relief, your real retention will be a little better than shown, because those reduce taxable pay. Treat the figure as an accurate baseline and confirm the current rates and bands with the KRA, since they have shifted with recent Finance Acts.
Why did NSSF stay the same after my raise?
Because NSSF is capped. The contribution is 6 percent of pensionable pay only up to an upper earnings limit, which produces a maximum of KES 6,480 a month per employee at the rates this calculator applies. In the example it barely moves, from KES 6,000 at KES 100,000 to the KES 6,480 ceiling at KES 120,000, so it takes only KES 480 from the raise. Once your salary clears that ceiling, a further raise adds nothing to NSSF, so almost the entire deduction wedge on the increase falls on PAYE, SHIF, and the Housing Levy instead.
Could a raise ever leave me worse off in Kenya?
No. Because PAYE is progressive, only the income above each threshold is taxed at the higher rate, so a higher gross always produces a higher net. You can keep a smaller share of each successive raise, which is what the retention rate shows, but you never go backwards on take-home from a pay rise alone. Any real "worse off" situation would come from losing a separate means-tested benefit, not from the tax on the raise itself.