All-in effective rate calculator
The rate you were sold is one line item of six. Your true cost of taking cards is every statement line (merchant service charge, authorisation pence, PCI fee, terminal rental, gateway and statement fees, plus any minimum-charge top-up) divided by your card turnover. Enter your own statement figures below and get your all-in effective rate instantly, next to the headline rate you thought you were paying.
The calculator runs entirely in your browser; nothing you type is sent anywhere. Typical UK line-item ranges shown beside the inputs reflect the Payment Systems Regulator card-acquiring market review findings and published acquirer pricing; your statement is the authoritative source for your own figures. Read the UK Card Processing Fee Index for the full range data.
The formula
Monthly cost = max(V × R%, MMSC) + (T × Auth) + Terminal + PCI + Other Effective rate = Monthly cost ÷ V × 100
- V = monthly card turnover; T = transaction count (V divided by average transaction)
- R% = headline MSC rate; the max() applies the minimum monthly service charge floor
- Auth = authorisation pence per transaction, charged on every authorisation
- Terminal, PCI, Other = the flat monthly lines from your statement
Why the gap between headline and effective rate grows as you shrink
Flat fees do not scale with volume, so they weigh more on smaller merchants. The same contract (1.4% MSC, 3p auth, £15 terminal, £4.95 PCI, £20 MMSC) produces very different effective rates:
| Monthly volume | Avg ticket | Monthly cost | Effective rate | Gap vs 1.4% headline |
|---|---|---|---|---|
| £1,000 | £10 | £42.95 | 4.30% | +2.90 points (MMSC floor bites) |
| £4,000 | £15 | £83.95 | 2.10% | +0.70 points |
| £8,000 | £20 | £143.95 | 1.80% | +0.40 points |
| £25,000 | £35 | £391.38 | 1.57% | +0.17 points |
Source: MerchantHQ effective rate calculator, worked example contract
Monthly cost = max(MSC, MMSC) + authorisation fees + terminal rental + PCI fee. Reproduce any row by entering the figures into the calculator above.
View as plain-text Markdown
### Same contract, four merchant sizes: 1.4% MSC, 3p auth, £15 terminal, £4.95 PCI, £20 MMSC | Monthly volume | Avg ticket | Monthly cost | Effective rate | Gap vs 1.4% headline | | --- | --- | --- | --- | --- | | £1,000 | £10 | £42.95 | 4.30% | +2.90 points (MMSC floor bites) | | £4,000 | £15 | £83.95 | 2.10% | +0.70 points | | £8,000 | £20 | £143.95 | 1.80% | +0.40 points | | £25,000 | £35 | £391.38 | 1.57% | +0.17 points | Source: MerchantHQ effective rate calculator, worked example contract Monthly cost = max(MSC, MMSC) + authorisation fees + terminal rental + PCI fee. Reproduce any row by entering the figures into the calculator above.
At £1,000 a month the "1.4% deal" really costs 4.3%, more than double a no-contract 1.69% reader with no fixed fees. At £25,000 a month the fixed fees nearly vanish into the volume. This is why the same contract can be simultaneously a good deal and a bad one, and why comparing headline rates across providers tells you almost nothing.
“The result is only as honest as the statement you copy it from. Acquirers split the same margin across different line names, so check for scheme-fee pass-through, dormancy fees and seasonal minimums hiding under other labels before trusting a low result. The model also excludes chargeback fees, AMEX surcharges and refund leakage, which matter for high-risk and high-refund trades, and it treats interchange-plus pricing as a single blended input, which understates variation if your card mix swings month to month. Use it to find the gap, then verify against three real months of statements.”
What to do with your number
- Under 2% all-in: broadly competitive for sub-£25k monthly volume. Check the contract end date and any exit fee before relaxing.
- 2% to 2.5% all-in: worth a renegotiation conversation, especially if your volume has grown since you signed. Acquirers reprice for merchants who quote their effective rate back at them.
- Above 2.5% all-in: you are paying for line items that competitive deals waive. Run the fees calculator to see what no-contract readers would charge for the same volume, and compare against the total cost of acquiring worked examples.
- MMSC top-up showing in your result: your volume is below the floor. Either negotiate the MMSC away or move to a provider with no minimum (most per-transaction readers).
Frequently asked questions
What is an all-in effective rate?
Your total monthly card-processing cost (every line on the statement: MSC, authorisation fees, PCI fee, terminal rental, gateway and statement fees, any minimum-charge top-up) divided by your monthly card turnover, expressed as a percentage. It is the only number that is comparable between providers, because each provider distributes its margin across different line items.
Why is my effective rate higher than the rate I was sold?
Because the headline rate is one line of five or six. A 1.4% headline deal with a 3p authorisation fee, £4.95 PCI fee, £15 terminal rental and a £20 minimum monthly service charge can land anywhere between 1.6% and 3% effective depending on your volume and ticket size. The smaller your volume and average transaction, the wider the gap.
What is the authorisation (auth/PA) fee?
A pence-per-transaction fee charged every time a card is authorised, whether or not the sale completes. UK acquirers typically charge 1p to 4p per authorisation. It looks trivial but on a £6 average ticket a 3p auth fee adds 0.5% to your effective rate, often more than the difference between two headline quotes.
What is the minimum monthly service charge (MMSC)?
A floor on your monthly MSC. If your percentage fees come to less than the MMSC (commonly £10 to £25), the acquirer charges you the difference as a top-up. It only bites below a break-even volume (MMSC divided by your headline rate), so a £20 MMSC on a 1.5% rate is irrelevant above £1,333 monthly volume but punishing for a stall taking £400 a month.
Should I include the PCI fee even though I am compliant?
Include whatever your statement actually shows. Many UK acquirers charge a monthly PCI compliance or management fee (£4.95 to £15) even when you complete the self-assessment questionnaire, plus a separate, larger non-compliance fee (£20 to £40) if you do not. Both belong in the effective rate because you pay them either way.
What counts as a good effective rate in 2026?
Depends on volume and ticket size. As rough UK guides: under £4k monthly volume, 1.7% to 2.0% all-in is normal on a no-contract reader; £4k to £25k monthly, 1.5% to 1.9% all-in is achievable on a bundled deal; above £25k monthly, interchange-plus should land you under 1.5% all-in for consumer-card retail. If this calculator puts you well above those bands, you have a negotiating case.
Paying more than 2% all-in? Get it repriced
Send your monthly volume, average ticket and trade. Our account team benchmarks your effective rate against the acquirer panel for your band and sector, and surfaces the two or three providers that beat it. No obligation, no upfront fees.
Open quote form →Director, MerchantHQ
Oliver leads MerchantHQ's terminal testing and acquirer comparison. With a background in UK commercial finance and merchant payments, he oversees terminal reviews, switching guidance and high-risk vertical mapping.
Last reviewed: 11 June 2026