UK estate planning: ISA or pension first?

These nine variants model a retired UK couple, both age 72 in January 2026, with roughly £650,000 of investable assets plus secure income from two full State Pensions and defined-benefit pensions. The planning question is not "Can we retire?" but which wrapper to spend first when normal living costs are already covered.

The baseline income floor is about £4,500/month before tax, close to the research handoff's combined State Pension plus DB range. The presets then add real spending between £4,700 and £5,000/month, late-life care reserves, accessibility work, and different gifting patterns. In practice, that means the estate outcome depends less on earning more and more on how aggressively you reduce taxable assets while keeping flexibility for longevity, care, and family support.

One date matters: April 6, 2027. The current educational rule of thumb that "unused pension money is better for estate planning than ISA money" is no longer timeless, because the government has published legislation to bring most unused pension funds and death benefits into scope for Inheritance Tax from that date. So this pack treats ISA first, mixed draw, and pension first as planning styles to compare, not as a universal answer.

Quick variant comparison

How to read this: Planned gross/mo is the total monthly spending already baked into that branch, including gifts and tax friction. Safe/mo is the model's buffer-safe monthly spending level after all the one-off costs already listed in that variant. Liquid at 95 is the projected investable capital remaining at age 95 in today's money. The simulator does not model UK wrapper tax law or inheritance tax directly, so the differences below are proxies built from gifting pace, spending comfort, and withdrawal-tax friction.

Who this scenario is for

• A retired UK couple in their early 70s with normal bills already covered by secure pension income.
• You still hold meaningful DC pension, ISA, and taxable investment assets and expect inheritance tax to matter.
• You want to support adult children or grandchildren, but not at the cost of running short if one partner lives into their 90s or needs care.
• You need an educational framework for sequencing assets, not individualized estate-planning or trust advice.

Financial profile

• Secure income floor: about £23,946/year from two full new State Pensions plus roughly £30,000/year of combined DB income, which is why salary is not modeled at all.
• Spending benchmark: the research handoff anchors retired-couple spending around the PLSA's Moderate and Comfortable ranges, so the presets cluster around £4.7k-£4.9k/month in today's money.
• Asset base in the model: £650,000 of investable assets. This deliberately excludes any house value so the comparison stays focused on liquid estate-planning choices.
• Late-life realism: every branch includes family support, accessibility work, and a later-life care reserve because the main danger here is over-optimizing tax while underestimating flexibility needs.

What the numbers show

The most important result is that all three planning styles can work if the couple already has secure income and meaningful assets. In the March 2026 analysis pass, every variant stayed above zero, the lowest capital point was still about £373k in Pessimistic · ISA first, and even the most conservative branch still finished with nearly £449k at age 95. The harder question is which trade-off you want:

• ISA first usually gives the cleanest route to shrinking the taxable estate, because gifts and discretionary spending come out of capital that would otherwise stay inside the estate. That is why these presets use the highest ongoing gifting pace - and why the base case ends with the lowest liquid capital at 95.
• Mixed draw is the most balanced branch. It assumes you use ISA, taxable accounts, and pension allowances gradually rather than trying to win the tax game with one wrapper alone, and in this pack it leaves the highest base-case liquid capital at 95.
• Pension first is not "wrong" - especially if simplicity matters or if you expect the April 6, 2027 pension-IHT reform to narrow the old estate-planning advantage of untouched pension pots. But it often means more taxable withdrawals sooner, so this branch carries extra tax friction and leaves less room for gifting.

Compounding still matters even late in life: the base variants earn about £423k of lifetime interest in ISA first, £456k in Mixed draw, and £442k in Pension first. Because the simulator pools assets, use the results directionally. If your own ISA is small and the pension is large, the real-life case for spending ISA first can still be stronger than the model suggests. If your pension is already close to an eventual IHT problem, the gap between mixed draw and pension first may narrow.

The strategy

ISA first - strongest estate reduction, highest gifting pace

This branch assumes the couple covers discretionary spending, gifts, and one-off family support from ISA/GIA money first while leaving the DC pension as the more flexible later-life reserve. In the preset that means £1,400/month of gifting through age 84, a £60,000 family housing gift at age 76, and still keeping money aside for a £75,000 care shock at age 84.

The upside is straightforward: if the secure income floor already covers most living costs, spending non-pension assets earlier can reduce the taxable estate faster. The downside is behavioural rather than mathematical - some households dislike watching the ISA shrink even when the long-term logic is sound.

Mixed draw - the most robust if you value optionality

This branch assumes the couple uses each wrapper gradually. Gifts slow to £900/month, the family gift falls to £40,000, and the model adds £125/month of withdrawal-tax friction to reflect the real-world messiness of combining taxable pension income with taxable-account sales.

That makes Mixed draw a useful default for readers who care about estate planning but do not want a brittle rule. It preserves more flexibility if tax rules change again, if care costs arrive earlier than expected, or if one partner becomes the long-term survivor and wants a simpler income plan.

Pension first - simpler narrative, but tax drag arrives sooner

This branch assumes you start using more taxable pension money earlier, keep more ISA liquidity in reserve, and accept that the estate-planning edge of untouched pensions may be weaker after April 6, 2027 than it was under the pre-reform framing. Gifts therefore fall to £500/month, the family gift drops to £25,000, and the model adds £350/month of tax drag on earlier pension withdrawals.

For some couples, that trade is worth it. If simplicity, spending confidence, or beneficiary timing matter more than maximizing estate efficiency, pension first can still be the easier plan to live with. The risk is paying more tax sooner while still ending up with a sizeable taxable estate later.

UK-specific notes

• Inheritance Tax framing: this page is educational only. It uses the March 2026 research handoff, which notes current UK inheritance-tax rules plus the government's published April 6, 2027 pension change. Recheck the implementation status before treating any wrapper rule as settled.
• Gifts from income: the scenario treats regular gifting as feasible only because secure pension income already covers normal spending. In real life, the "normal expenditure out of income" exemption depends on pattern, affordability, and record-keeping.
• CGT and taxable accounts: the Mixed draw branch includes a small monthly friction number because drawing from GIAs can trigger capital-gains management work even when the simulator cannot model allowances directly.
• Care costs: these presets include explicit care reserves because the estate-planning mistake to avoid is gifting too aggressively and then losing flexibility if one partner needs paid care.
• House value: no home equity is modeled here. If the house is a major part of your estate, your actual inheritance-tax exposure may be higher than the simulator's liquid-capital figure suggests.

Personalise this for your own plan

• Change the secure-income floor first: edit the DB pension income if your household gets more or less than the modeled £2,500/month on top of the two State Pensions.
• Replace the gifting cadence with your own: if you expect to give nothing, halve the gifts, or gift in larger one-off chunks, adjust those entries before reading too much into the ranking.
• Stress-test longevity and care: push deathAge to 98 or 100, move the care reserve earlier, and watch which branch still feels comfortable.
• Split wrappers mentally, even though the simulator cannot: if your ISA is tiny but your pension is very large, treat the ISA-first results as more aspirational and the mixed-draw results as the more realistic baseline.
• Model policy uncertainty conservatively: if you think the April 6, 2027 reform may materially reduce the pension's estate-planning edge, use Mixed draw or Pension first as your starting point and compare from there.

This scenario is an educational model, not personal financial or estate-planning advice. It simplifies UK tax, inheritance, gifting, and care-cost rules so you can compare drawdown styles before speaking with a qualified professional.