Plain, unbiased UK investing guidance: index funds, stocks and shares ISAs, SIPPs and platform comparisons. Calm, evidence-led, no hype.
A calm, fee-first comparison of the best stocks and shares ISA platforms in the UK for 2026, with verified charges for Trading 212, Vanguard, AJ Bell, HL and more.
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A plain, fee-by-fee comparison of Trading 212, InvestEngine and Vanguard for UK ISA and SIPP investors. Real charges, real trade-offs, no hype.
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A plain, step-by-step guide to opening a SIPP in the UK: who can open one, the tax relief, picking a platform, and your first contribution.
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Free UK investment platform fee calculator: enter your pot size and we work out the yearly cost on Trading 212, InvestEngine, Vanguard, AJ Bell, HL and interactive investor, ranked cheapest first.
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A UK investment growth calculator that projects your ISA or SIPP pot from a starting sum and monthly contributions, with fees and inflation deducted so you see the real, spendable value.
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A UK pension tax relief calculator that shows the real cost of a SIPP or pension contribution after 20% relief at source plus any higher or additional rate relief you claim back through Self Assessment.
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Work out how long to reach 100k or any investment target, from your starting pot, monthly contribution and expected return, with the monthly amount that would get you there faster.
Read moreRational GB is for people in Britain who want to invest sensibly without being sold to. We cover the things most DIY investors actually need to get right: opening your first stocks and shares ISA or SIPP, picking low-cost index funds, and working out which investment platform suits how much you have and how often you’ll trade. Every recommendation is grounded in evidence and total cost, not in whatever fund a provider happens to be pushing this month.
If you’re somewhere between 25 and 55, saving steadily and trying to decide between brokers or between funds, this is written for you. We compare the major UK platforms on fees, features and quirks, explain how ISAs and SIPPs actually work, and walk through index investing in language you don’t need a finance degree to follow. No stock tips, no get-rich-quick angles, no panic when the market wobbles.
The stance is simple: think, don’t gamble. Markets go up and down, the financial press shouts about both, and most of that noise costs you money if you act on it. We’d rather help you build a plan you can stick to for decades and then leave it alone.