Written by AfterTaxSalary Editorial. Reviewed against official UK sources. Editorial standards · Methodology
Practical guidance for modelling take-home pay when personal allowance starts tapering above GBP100,000.
Above GBP100,000, personal allowance taper can change effective deductions significantly. This guide focuses on practical scenario planning.
As income rises above GBP100,000, personal allowance is reduced, which increases effective deductions on that slice. This catches many people by surprise when pay rises feel less valuable than expected.
The effect is often described informally as a high effective deduction zone. Whether this is temporary or persistent for you depends on salary structure, bonus pattern and pension strategy.
For planning, it is essential to compare multiple scenarios rather than relying on one headline estimate.
Use salary points across the range, such as GBP100k, GBP110k, GBP120k and GBP125k. Compare monthly net delta between each point, not only annual totals.
Then test pension contribution changes. For many employees, pension choices materially alter taxable pay and therefore the shape of net outcomes in this range.
If variable bonus is likely, include conservative and optimistic bonus cases. This avoids overestimating stable monthly cashflow.
When choosing between offers near this boundary, compare package structure as well as gross value. A slightly lower gross offer with stronger pension support may produce better long-term outcomes.
Use a transparent checklist: salary, expected bonus reliability, pension design, student loan status and tax code. Without this, comparisons are often inconsistent.
The strongest negotiations are grounded in net-pay evidence. Showing realistic monthly deltas is usually more persuasive than discussing gross salary in isolation.
Because personal allowance is reduced as income rises in this range, which raises effective deductions on that slice in addition to normal marginal tax effects.
Run matched scenarios at several salary points and compare net monthly differences. A single annual estimate can hide threshold effects.
Yes. Pension settings can alter taxable pay and therefore change net outcomes in taper territory. Always model pension assumptions explicitly.
Yes. Use the scenario links in this guide to open prefilled states, then adjust salary, region, loan and pension settings.
Yes. Core content is rendered in HTML and linked to salary/city/tool pages for crawlable internal navigation.
Tax region, tax code, student loan plan, pension contribution and salary sacrifice are the key assumptions to check first.