SIPP vs Workplace Pension — The 2026 Tax-Relief Maths
You can put money into a Self-Invested Personal Pension (SIPP) and into your workplace pension. They both get tax relief — but the way the relief flows changes the practical maths. Here’s how it plays out in 2026.
How Tax Relief Works in a Workplace Pension
Two flavours:
- Net pay arrangement (common with salary-sacrifice schemes): your contribution comes out before income tax is calculated. You get full marginal-rate tax relief automatically.
- Relief at source: contributions go in net of basic-rate tax (20%). Higher and additional-rate taxpayers reclaim the extra relief through self-assessment.
For a 40%-rate earner contributing £400 into a relief-at-source workplace pension:
- £400 in pocket → HMRC tops it up by £100 (basic 20%) → £500 in pension
- £100 extra relief claimed via self-assessment → £100 refunded to your bank
- Net cost to you: £300 for £500 in pension
How a SIPP Treats Tax Relief
SIPPs always use relief at source. You contribute net (£400), HMRC adds 20% (£100), so £500 lands in the SIPP. Higher and additional-rate taxpayers claim the extra via self-assessment.
In other words: the relief mechanism is identical between SIPP and a relief-at-source workplace pension.
So Why Choose One Over the Other?
| Factor | Workplace pension | SIPP |
|---|---|---|
| Employer matches | Yes (usually 3%–5%) | No |
| Salary sacrifice (NI savings) | Often available | No |
| Fund selection | Limited (5–25 funds) | Unlimited (most ETFs, funds, shares) |
| Platform fees | Often free (employer subsidises) | £0–£150/yr platform fee |
| Tax relief speed | Automatic if net-pay | Same as SIPP if relief-at-source |
| Tax relief above 20% | Self-assessment required (RaS only) | Self-assessment required |
The Employer Match Is the Real Win
The employer match in a workplace pension is free money. A typical scheme:
- You contribute 5% of salary → employer adds 3%
- £45,000 salary → £2,250 from you, £1,350 from employer, £563 basic-rate relief
- Total going in: £4,163 per year
- Cost to you (after basic-rate relief): £1,800
- Total in pension: £4,163
You can’t replicate that match in a SIPP. Always contribute enough to your workplace pension to capture the full match before touching a SIPP.
When the SIPP Adds Value
Beyond the employer match, the SIPP is useful if:
- You want broader fund choice (your workplace scheme has only “default” funds you don’t like)
- You’re self-employed (no workplace pension to compare against)
- You want to consolidate old pensions from previous employers (transfer-in to a SIPP for simpler management)
- You’re a higher-rate taxpayer wanting more headroom under the annual allowance (£60,000 for 2026)
Salary Sacrifice — The 2026 Trick Worth Knowing
If your employer offers salary sacrifice for pension (and most do), this gives you a 2% NI saving on top of income-tax relief. For higher-rate earners, salary sacrifice provides additional NI savings of around 2% on the sacrificed amount.
For a £80k earner sacrificing £8k into pension:
- Income-tax saving: £3,200 (40%)
- NI saving: ~£160 (2% on sacrificed amount above primary threshold)
- Total cost-vs-take-home: £4,640 for £8,000 in pension
The SIPP path doesn’t include the NI saving.
Bottom Line
For 2026 UK savers: max the employer match in the workplace pension first. Use a SIPP for additional contributions if you want better fund choice. If salary sacrifice is offered, prefer the workplace pension over SIPP for that portion — the NI saving compounds over a career.
