Unsocial Hours, ACH and ACHP
What Each Contract Pays — Band 3, pay point 1 (National)
| Contract | Gross annual | Of which pensionable | Take-home per month |
|---|---|---|---|
| 37 hours — base pay | £29,107 | £29,107 | £1,951 |
| 37 hours + 20% unsocial | £34,928 | £34,928 | £2,282 |
| 39 hours (2× ACH) + unsocial | £37,131 | £34,928 | £2,414 |
| 39 hours (2× ACHP) + unsocial | £36,816 | £36,816 | £2,369 |
| 41 hours (4× ACH) + unsocial | £39,334 | £34,928 | £2,545 |
Three separate things sit on top of a prison officer's base pay, and they behave differently.
Unsocial Working Hours (UWH) is an allowance of 20% of base pay for Bands 3 to 5, and 25% for Band 2 Operational Support Grades. It is pensionable, so it raises both your contributions and the pension you build.
Additional Committed Hours (ACH) pays for contracted hours above the 37-hour base week. Crucially, ACH is not pensionable. ACHP is the pensionable version of the same thing.
This is why the two 39-hour lines differ. The ACH contract pays £37,131 and the ACHP contract £36,816 — on the ACH version you take the money as cash now instead of building pension with it. Because only £34,928 of the ACH contract is pensionable, that officer also stays in the 4.60% alpha tier rather than crossing into 5.45%, which is worth around £420 a year.
Most calculators miss this and charge pension on the whole salary. This one splits your pay into the pensionable part and the ACH element, so the deduction is right.