Plan 2 + postgrad loan: your real marginal rate
Two student loans repay at the same time, each above its own threshold. With both running, a £35,000 → £42,000 rise keeps 53p in the pound — and the payslip line that explains it is the loans'.
The worked example
A master's graduate with a Plan 2 undergraduate loan (9% above £29,385) and a postgraduate loan (6% above £21,000), 5% pension on net pay:
On £35,000
Plan 2 + postgrad · 5% pension
On £42,000
same loans, same pension
The loans line jumps £1,050 on a £7,000 rise — 15% of the entire raise, more than NI takes. Across the rise the marginal stack is 20% tax + 8% NI + 9% Plan 2 + 6% postgrad = 43p of every extra pound, before your own pension.
Why two loans is its own tax band
Each loan repays independently above its own threshold, so from £29,385 upward both run at once and your marginal deduction rate is 43% — within touching distance of a higher-rate taxpayer's, on a £35,000 salary. People hear '9% student loan' and budget for one line; the second one is the surprise. The thresholds did rise this April (what changed for 2026/27), which trims the bill slightly — but the marginal rate above them is untouched.
It also reshapes decisions this site exists for: a rise, an extra day, overtime — all return 53p in the pound, which moves break-even salaries and changes whether a longer commute can pay for itself. And it makes salary sacrifice unusually valuable: sacrificed pension escapes both loans as well as NI — a 23% bonus on every sacrificed pound that net-pay schemes leave on the table.
Run this scenario with your own numbers
The button opens the calculator pre-loaded with this exact worked example — change anything, including the ratings and your priorities, and every figure recomputes live, in your browser. Nothing you type is uploaded.