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ISA vs SIPP: where should the next £1,000 go?
Not a lecture: a decision. Your band, your horizon and your match, ranked into where the next pound actually works hardest, reasoning included.
Higher rate starts above £50,270 (2026/27). Scottish bands differ.
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ISA by a nose
At basic rate the SIPP's head start (£1,000 becomes £1,250) is partly clawed back by income tax in retirement, while the ISA is tax-free out and never locked. Unless retirement is close (relief now, likely lower band later), take the flexibility.
Allowances behind this: ISA £20,000 a year (2026/27); pension annual allowance £60,000 with relief at your marginal rate; minimum pension age 57 from 2028. This is a framework, not personal advice: big pots, tapered allowances and Scottish bands all deserve a professional.
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Educational information, not financial advice. Figures current as of July 2026 where dated; allowances and rates change, so check the source before acting.