Drawdown mechanics 9 February 2026 5 min read

UFPLS vs flexi-access drawdown: what's the difference?

Two technical-sounding ways to take money from a UK pension. The difference comes down to a single question: when does the 25% tax-free cash actually leave the pension - up front, or alongside every withdrawal?

Once you reach pension access age (currently 55, rising to 57 in 2028), most UK personal pensions and SIPPs let you take money out in one of two ways: flexi-access drawdown or UFPLS (Uncrystallised Funds Pension Lump Sum). They're both perfectly legitimate, and most providers support both. The choice affects when you pay tax, not how much.

Flexi-access drawdown: tax-free cash out, taxable pot for later

Flexi-access drawdown is the older, more familiar option. The mechanic is:

1. You crystallise some or all of your pension pot.
2. At crystallisation, 25% of the crystallised amount comes out as tax-free cash - you can spend it, move it to an ISA, pay off a mortgage, anything.
3. The remaining 75% moves into a crystallised pot inside the pension, still invested and growing.
4. You then draw income from the crystallised pot as needed. Every withdrawal is taxed as income at your marginal rate.

The defining feature: tax-free cash is taken up front. Once the 25% is out, future withdrawals from the crystallised pot are fully taxable.

You can crystallise in chunks. Crystallise £100,000 today, take £25,000 tax-free, and the other £75,000 sits in the crystallised pot. Crystallise another £100,000 next year, take another £25,000 tax-free, and so on - up to the £268,275 Lump Sum Allowance over your lifetime.

UFPLS: tax-free cash and taxable income, every withdrawal

UFPLS is the alternative. With UFPLS, you don't crystallise the whole pot in advance. Instead, every individual withdrawal automatically gets split into a 25% tax-free portion and a 75% taxable portion at the moment of withdrawal:

1. You ask for £20,000 from your pension.
2. £5,000 (25%) comes out tax-free.
3. £15,000 (75%) comes out as taxable income, added to your other income for the tax year.
4. The remaining pension pot stays uncrystallised. Next withdrawal repeats the same 25/75 split until you've used up your LSA.

The defining feature: tax-free cash drips out alongside taxable income. There's no “take the lump first” moment.

The practical difference

The two routes produce identical tax outcomes if your behaviour is identical. The differences only emerge when behaviour diverges:

• Flexi-access suits people who want a lump sum now. You crystallise, take the tax-free portion straight away, and have it available for a mortgage payoff, house purchase, or simply moving the money into an ISA where it grows tax-free outside the pension wrapper.
• UFPLS suits people who want steady income with the tax-free element built in. Each year's £20,000 withdrawal nets £5,000 tax-free + £15,000 taxable, which keeps total taxable income lower than if you'd front-loaded the tax-free cash and then drew fully-taxable amounts every year.
• Personal Allowance interaction matters. Under UFPLS, the 25% tax-free portion doesn't count toward your Personal Allowance, but the 75% taxable portion does. Withdraw £16,760 via UFPLS - £4,190 tax-free + £12,570 taxable - and the taxable portion fully uses your £12,570 Personal Allowance with zero tax due. The same gross under flexi-access (after you've already taken the lump) would all count toward Personal Allowance.

Why most providers default to flexi-access

Two reasons. First, flexi-access has been around longer and is what advisers tend to default to in conversation. Second, the “take 25% tax-free up front” idea is what most people already half-understand about pensions, so it's the easier sell.

UFPLS is the more tax-efficient option for someone drawing steady income through retirement without a lump-sum need, but it requires explaining how the 25/75 split works at each withdrawal. Many providers offer it; some default away from it.

How Excelergy models drawdown

The Excelergy planner uses a UFPLS-style mechanic by default for automatic drawdown during retirement. When the engine needs to fund a year's spending and your existing crystallised pot can't cover it, it crystallises just enough additional uncrystallised pension to make up the gap - with the 25/75 split applied to the crystallised portion that year.

If you want to model an explicit up-front flexi-access crystallisation - for example, take £100,000 tax-free at age 60 to pay off a mortgage - you add it as a Crystallisation event in the Event card. The model treats the 25% tax-free cash as leaving the system (External destination) or moving to a chosen pot (Cash ISA, Stocks ISA, Current Account), and the 75% taxable portion goes into your Crystallised pot to be drawn later.

The result is that you can experiment with both approaches: leave events empty for a pure UFPLS retirement, or add events to model flexi-access lump sums at specific ages. The tax outcomes follow the standard UK rules either way.

Which one to use in practice

For most retirees drawing steady income without a one-off cash need, UFPLS produces slightly better tax outcomes because the 25% tax-free portion spreads across every withdrawal year. For people with a specific large purchase planned at retirement, flexi-access lets you take that lump sum cleanly without distorting subsequent income withdrawals.

Many people end up using both: one flexi-access crystallisation for an early-retirement lump-sum need, then UFPLS-style drawdown for ongoing income from whatever's left. The model handles either pattern.