Forex spread betting vs CFDs: which is cheaper?

For profitable UK-based traders running standard CFD books, that delta alone erases the headline spread advantage on most retail platforms. Spread betting, exempt from both CGT and Stamp Duty, has not been touched. The tax efficiency gap is no longer marginal. It is the dominant variable for any UK or Irish resident running long-horizon forex exposure.

This analysis dissects the transaction cost stack across both instruments: spread width, commission load, overnight financing, currency conversion, and the tax friction layered on top. The verdict applies to retail accounts held by UK and Irish residents only. Spread betting remains legally restricted in most jurisdictions outside those two markets. For tax treatment in any other region, the entire argument collapses.

The Tax Efficiency Layer: 2024 CGT Reset and Net Profit Retention

Spread betting wins on tax handling by structural exemption, not by fee engineering. Profits fall outside the scope of Capital Gains Tax. Stamp Duty on UK equities does not apply. The carve-out for "betting on financial markets" against an index, currency, or commodity price movement is maintained under existing UK betting legislation.

CFDs do not share that status. Net annual gains are computed under standard CGT rules and taxed at the rates active in the relevant tax year. Following the October 2024 Budget, the higher-rate band climbed to 24% from the previous 20%, and the basic rate to 18% from 10%. The shape of the after-tax profit curve for a profitable CFD book shifted accordingly.

For a UK higher-rate taxpayer whose net CFD gains feed the higher band, the rate change moves a meaningful slice of net profit to HMRC. The arithmetic is illustrative rather than prescriptive: a £20,000 net gain, treated as if fully taxable at the higher rate with no allowance offset, would produce a £4,800 CGT bill under the new rate versus £4,000 under the old. A basic-rate taxpayer in the same scenario would see a £3,600 bill against the previous £2,000. The actual liability in any given year depends on the taxpayer's full capital gains position, the annual exempt amount, any carried-forward losses from prior years, and the size of the gain relative to the basic-rate band. The point is directional, not absolute: the rate increase applied to the same trading output, with no change in execution quality or strategy.

For a profitable UK retail trader whose net CFD gains sit comfortably above the higher-rate threshold, the direction of the change is unambiguous. The percentage taken by HMRC has climbed. The percentage retained by the trader has fallen by the same amount. Over a multi-year horizon, that compounds into a meaningful gap on the spread betting side, where the equivalent profit is retained in full.

CFD losses retain one useful counterweight. They can be offset against other capital gains in the same tax year, including gains realised outside the trading account. Unused losses can also be carried forward indefinitely. That mitigation applies to losses only, not to the underlying rate. It does not neutralise the rate increase. It merely softens the blow on losing years and produces a real tax value on a net negative book.

The future of the spread betting exemption is not anchored in a way that locks it in permanently. Government has reviewed gambling taxation repeatedly. The carve-out for financial spread betting has survived those reviews, but no analyst can promise it will continue indefinitely. For planning purposes, the exemption is in force now and appears politically uncontroversial, but it sits on a different legal footing from a CGT rate that has just been raised by an explicit fiscal event. Circumstances can change.

Spread betting's tax advantage is not a fee reduction. It is a structural margin lift on net profit, calibrated against HMRC rates that just moved against CFD holders.

Currency Conversion: Why Spread Bets Denominate in Base Currency

CFDs are priced in the currency of the underlying asset. A UK resident trading EUR/USD CFDs on a sterling-denominated account pays the broker for FX conversion on every transaction, including rolling positions overnight. The conversion fee structure varies by broker but the retail band sits between 0.5% and 0.7% per conversion event. On a £100,000 notional EUR/USD round-turn, that is £500 to £700 in conversion drag before spread or commission enters the calculation.

Spread betting denominates every position in the account's base currency. GBP/USD is quoted in pounds per point. The broker does not run a conversion. The fee simply does not appear on the statement. For a trader running a diversified book across multiple non-GBP pairs, that removes a continuous drag on returns that compounds with trade frequency.

The drag is not theoretical. A trader running ten round-turns per month on EUR/USD, average notional £50,000 per round-turn, with a 0.5% conversion rate applied to the notional, runs into a per-month conversion bill measured in the low thousands of pounds against the raw figure. The annualised total is a recurring, performance-denting line item that simply does not exist on a spread bet, where the sterling quote absorbs the same exposure without any conversion step. The absolute number depends on the notional base, the broker's fee band, and the round-trip frequency, but the directional effect is unambiguous: every round-turn on a non-GBP pair through a sterling CFD account pays a friction that the spread betting equivalent does not.

For a trader holding positions overnight, the conversion is also applied to the swap calculation when the underlying rate and the account currency differ. That adds a second layer of FX friction on multi-day trades, again with no equivalent cost on the spread bet. The compounding effect across a year of active trading is not marginal. It is a structural cost that is fully avoidable by the choice of wrapper.

Commission Structure: Raw Spread CFDs vs. All-in Spread Betting

This is the section where the comparison reduces to a hard technical breakdown. Three account types sit on the table: spread betting, standard CFD, and raw spread CFD.

Spread betting is almost universally commission-free across retail providers. Cost is entirely embedded in the bid-ask spread. The wider the spread, the higher the friction. There is no separate per-trade fee. There is no volume rebate structure for retail accounts. The exceptions are rare and tend to sit on niche platforms or professional-tier products rather than the standard retail offering.

Standard CFD accounts mirror the spread betting model, with all costs embedded in the spread. Major forex pairs on the largest retail platforms quote in the 0.6 to 1.2 pip range. The broker's revenue is the spread itself, plus overnight swap markups.

Raw Spread or ECN accounts deliver tighter spreads, often starting at 0.0 pips on EUR/USD, but layer a fixed commission on top. Typical retail rate: $2.50 per lot per side, equivalent to roughly £4.10 per round-turn on a standard lot at current GBP/USD rates. The trade-off is mechanical: pay less in spread, pay more in commission.

The break-even point sits where the commission saving on a raw account exceeds the spread widening on a standard account. On EUR/USD, the typical spread differential between a standard CFD account and a raw account is roughly 0.5 to 0.8 pips. At a notional of £100,000 per lot, that translates to a £4 to £6.50 cost differential per round-turn in favour of the raw account, before commission. Commission on the raw account is £4.10. The margin is thin. On some sessions it is positive. On others, the spread widens enough to flip the sign.

For traders running on instruments beyond the major pairs, the calculus shifts. Cross rates, emerging market currencies, and exotic pairs carry wider spreads on all account types, and the raw account's commission saving narrows. On EUR/USD, the comparison is genuinely competitive. On USD/TRY or USD/ZAR, the standard CFD's all-in spread often wins on cost alone.

For share CFDs, the cost structure shifts. Brokers typically charge a commission of 0.10% per side, with a £10 minimum. On a £5,000 share trade, the £10 minimum applies on each side. On a £50,000 trade, the percentage rate applies, producing £50 per side. Spread betting on shares has no commission and no minimum, but the bid-ask spread is wider to compensate. For high-volume share traders running institutional-size books, the percentage commission on CFDs becomes punitive. For smaller, less frequent share trades, the spread betting zero-minimum structure wins.

Overnight Financing: Swap Mechanics Across Both Instruments

Both instruments carry overnight holding costs when a spot or cash position is held past the daily cut-off, typically 10 PM UK time / 5 PM EST. The mechanics are identical: positions are debited or credited based on the interbank benchmark rate plus or minus a broker markup. The markup band sits at ±2.5% to 3% above the underlying rate, depending on the asset and the broker.

This cost layer is neutral across both products. There is no swap advantage held by either side. Holding a EUR/USD long position overnight on a spread bet produces the same swap debit as holding the equivalent CFD, all else equal. The comparison only diverges if the broker applies different markup bands to its spread betting book versus its CFD book. That pattern is rare across major providers but not unknown on smaller platforms where the spread betting book is treated as a secondary product.

For traders running multi-day positions, the swap markup is the dominant cost component, often exceeding the spread by a factor of 10 over a holding period of one week. The product choice does not change this. The broker choice does. Triple-Wednesday swaps, end-of-month rollover conventions, and the LIBOR-to-SOFR transition markers all behave identically across the two wrappers on the same broker.

The swap field is also where broker opacity peaks. Markup is rarely itemised on a standard trading dashboard. The trader who wants to know the spread between broker rate and interbank rate usually has to ask the broker directly or compare against a benchmark swap rate feed. That opacity is shared by both products.

Margin Requirements and Position Sizing

UK retail margin requirements are regulated by the FCA, not ESMA, after the post-Brexit divergence. Irish retail accounts remain under the Central Bank of Ireland's implementation of the ESMA product intervention measures. The two regimes produce similar but not identical limits, and the relevant regulator depends on the legal entity holding the client account, not the client's nationality or residence.

For UK retail accounts under FCA rules, the leverage tiers on major forex pairs sit at 30:1 maximum (3.33% margin), minor pairs at 20:1 (5% margin), and commodities and indices vary by asset class. For Irish retail accounts under CBI rules aligned with ESMA, the same 30:1, 20:1, and asset-class-dependent tiers apply. The actual limit on a given position depends on the broker's passporting status and the account jurisdiction.

The wrapper is irrelevant to the margin calculation. Both spread bets and CFDs on the same underlying carry the same margin requirement for the same client type. A £10,000 position on EUR/USD requires £333 of margin under either instrument. The position sizing math is identical. The choice of product does not alter capital efficiency at the position level, and it does not affect the available leverage tier for retail clients.

For professional client classifications, where the retail leverage caps do not apply, the margin is set by the broker and the product type remains neutral. The professional tier is taxed differently and is treated separately in the verdict section below.

When CFDs Outperform Spread Betting

The tax and FX arguments dominate for most UK and Irish retail traders. Three scenarios reverse the verdict.

High-volume raw spread traders. A trader running 50 or more round-turns per week on major pairs can outpace the spread betting cost model on a raw CFD account. The commission load is fixed and known. The spread saving is measurable. Tax is paid but is a known percentage of net profit. The total transaction cost per round-turn can fall below the all-in spread on a spread betting account. Spread betting's tax exemption becomes a percentage gain on a smaller net profit, which may net less in absolute terms.

Professional or corporate traders. Tax exemption does not apply to all entity structures. Corporate accounts, professional client classifications, and certain trust structures are taxed differently. Spread betting's headline advantage assumes an individual retail taxpayer within HMRC scope. Outside that scope, the comparison reduces to transaction cost only, where CFDs win on raw accounts.

Traders outside the UK and Ireland. Where spread betting is not legally offered, the comparison does not exist. CFDs are the only option, and the cost question is settled by the local CGT or trading-income regime, which carries its own rates and allowances that this analysis does not cover.

Spread betting is not a cheaper product. It is a different tax wrapper, with the same execution layer underneath.

Stability Verdict

Spread betting holds a structural cost advantage for UK and Irish individual retail traders running standard account types. The tax exemption is currently in force and was unaffected by the October 2024 CGT adjustments. The absence of currency conversion fees removes a continuous drag. The almost universal commission-free model simplifies cost tracking and eliminates the spread-versus-commission trade-off for traders running low-frequency books.

CFDs outperform in narrow use cases: high-volume raw spread traders on major pairs, professional or non-UK-resident traders for whom the tax exemption does not apply, and traders operating outside the small set of jurisdictions where spread betting is legally offered. Outside those cases, the spread betting wrapper delivers a lower net cost on a profitable book.

Both products carry identical overnight swap mechanics, identical margin requirements at the retail level, and identical underlying exposure. The cost differential is a function of tax treatment and currency denomination, not of execution quality or chart stack capability. The choice is mechanical. For UK and Irish residents on standard accounts, spread betting is the lower-cost instrument for the typical retail book. For everyone else, the wrapper is irrelevant and the underlying CFD pricing, on a raw account, sets the floor.