The quick answer is "less than you think to open an account, more than you think to trade it well". Both halves matter, so here is the honest version.

Start with money you can afford to lose

This is not a disclaimer tucked at the bottom — it is the first rule. Brokers regulated in the UK and EU are required to publish the percentage of their retail clients who lose money trading CFDs, and those figures are consistently well over half. Whatever you deposit should be money whose loss would be disappointing, not damaging.

Opening an account vs trading it properly

Many brokers let you open a live account with a very small deposit. That is not the useful number. The useful number comes from position sizing:

Position size = (Account size × Risk %) ÷ Stop distance

With a sensible 1% risk per trade, the account size decides how much each trade can lose — and your broker's minimum position size decides whether you can actually trade that small.

The maths on a £250 account

  • 1% risk = £2.50 per trade.
  • The smallest position most brokers allow is a micro lot (0.01). On EUR/USD that is about $0.10 per pip — roughly £0.077 at a GBP/USD rate of 1.30.
  • £2.50 ÷ £0.077 ≈ 32 pips.

So on a £250 account, a single micro lot keeps you inside 1% risk only if your stop is about 32 pips or closer. A tighter stop is fine — you risk less than 1%. A wider stop means you are over 1% even at the smallest size the broker allows, and the only honest options are to skip that trade or accept the higher risk knowingly.

That is the real constraint on small accounts. It is not that you cannot trade — it is that the market will regularly offer trades whose correct stop is too wide for your size, and discipline means passing on them.

Why "just use more leverage" is the wrong fix

Leverage lets a small deposit control a larger position. It does not change what a pip is worth at a given position size — it only changes how large a position you are able to open, and an oversized position is how a small account gets wiped out quickly. UK-regulated brokers cap retail leverage on major currency pairs at 30:1 precisely because high leverage and small accounts are the classic way beginners are wiped out.

Position size, not leverage, is what you should be controlling.

A sensible path

  1. Demo first. Prove you can follow your own process for a few weeks with no money on the line. If you cannot follow rules on demo, a live account will not fix that.
  2. Start live small, deliberately. The first live account is for learning how it feels to follow a plan when the money is real. Expect it to be a learning cost.
  3. Keep risk fixed at 1–2% and let the account size dictate what you can take, not the other way round.
  4. Add money only after the process holds, not to recover losses.

What about prop firm challenges?

A funded-account evaluation lets you trade a firm's capital for a much smaller fee. It is a genuine route for many people — but the rulebook (daily loss limit, maximum drawdown) is the product, and most people who fail do so by oversizing or chasing a losing day, not by reading charts badly. Read every rule before you pay.

Key takeaways

  • Only deposit money you can afford to lose.
  • The useful question is not "how little can I deposit?" but "can I size trades at 1% with this account?"
  • On £250, a micro lot keeps you at 1% only with stops of roughly 32 pips or less on EUR/USD.
  • Control position size, not leverage.

Go further: Lesson 1.1 (brokers, platforms, account types and funded accounts) and Lesson 1.4 (position sizing) are both free in the Trovia Academy. Questions? Ask in the free public channel at t.me/troviatrading.

Educational content only — not financial advice. Trading carries a high risk of loss. Figures are illustrative; pip values depend on the pair, your account currency and current exchange rates.