How Fluxa compares. Honestly.

At a glance.

A truthful, side-by-side picture of who each provider is, what they charge, and the one or two things they each do better than anyone else. Headline pricing only here; the section below digs into effective rates for UK B2B businesses.

All UK card rates quoted are publicly listed headline rates as at May 2026. Stripe, Adyen, Square and GoCardless are trademarks of their respective owners and are referenced here for comparison only. Fluxa is not affiliated with any of them.

Pricing compared.

Headline rates rarely match what you pay. Fluxa is online checkouts only; everything below is the online-versus-online comparison. Real UK businesses taking online payments handle a mix of UK domestic cards, overseas-issued cards, business cards and consumer cards. They run subscriptions, take refunds, deal with disputes. This section shows what three real business profiles pay on Stripe versus Fluxa each month, with every line itemised.

Stripe’s headline 1.5% + 20p applies only to standard UK cards. Premium UK cards (corporate/commercial) are 1.9% + 20p. EEA-issued cards step up to 2.5% + 20p. Non-EEA international cards jump to 3.25% + 20p. If the customer pays in a non-GBP currency, add 2% for conversion. Need recurring billing, add 0.7%. Want fraud screening on Standard pricing, add 2p per transaction. Each is reasonable in isolation; together they push the effective rate well above the headline. Fluxa is 1.8% on every card. UK, EEA, US, anywhere. No surcharge, no FX markup if you settle in GBP, no add-ons. Disputes and chargebacks are included. No per-dispute fee, no representment fee, no Fluxa dispute handling markup. Where Stripe charges £20 per dispute received (returned only if you win), Fluxa does not add a chargeback markup and Tom drafts the rebuttal evidence pack for you to review and sign off.

Scenario one: low-ticket UK SaaS

£10,000 monthly card volume. 500 transactions averaging £20. This is a typical low-ticket SaaS price point: a £19/month developer tool, a £15/month content subscription, a £25/month productivity app. 95% UK domestic, 3% EEA, 2% non-EEA international. 0.4% dispute rate.

This is the profile where Stripe’s 20p per-transaction fee hits hardest. On a £20 charge, the 20p alone is 1% of the transaction value before the percentage rate even starts.

Scenario two: growing UK SaaS with subscriptions

£50,000 monthly card volume. 500 transactions averaging £100, mostly recurring. 88% UK domestic, 7% EEA, 5% non-EEA international. 0.5% dispute rate. Uses Stripe Billing (0.7% on recurring volume) and Radar for Fraud Teams (2p per screened transaction on Standard pricing).

Scenario three: established UK SaaS at scale

£200,000 monthly card volume. 1,000 transactions averaging £200, mostly recurring. 85% UK domestic, 9% EEA, 6% non-EEA international. 0.6% dispute rate. Uses Stripe Billing, Radar for Fraud Teams (2p on Standard pricing), Stripe Sigma for analytics (£11/month flat) and Stripe Identity for KYC on new customer onboarding (50 new customers per month).

Scenario four: B2B SaaS at enterprise scale

£500,000 monthly card volume. 2,500 transactions averaging £200, primarily recurring B2B subscriptions. Realistic B2B card mix: 85% UK domestic, with 25% of those on commercial/corporate cards which Stripe charges at the premium rate of 1.9% + 20p (not the headline 1.5%). 9% EEA, 6% non-EEA. 0.5% dispute rate. 100 new business customers per month requiring KYB. Uses Stripe Billing, Radar for Fraud Teams on Standard pricing, Stripe Sigma and Stripe Identity.

At this volume Fluxa custom pricing typically applies, taking the rate below 1.8%. The comparison below uses the published 1.8% standard rate as the conservative number; an actual custom-priced Fluxa contract puts the saving higher than what is shown.

Common Stripe add-ons not included in the scenarios above

The four scenarios above are conservative. They use Stripe Standard, do not assume currency conversion, do not assume instant settlements and do not include Stripe Tax. In practice many UK B2B SaaS merchants add one or more of the following:

• Premium UK cards (1.9% + 20p). The headline 1.5% + 20p only applies to standard UK consumer cards. UK commercial and corporate cards - which are common in B2B SaaS - are charged at 1.9% + 20p. Scenarios one to three above use the conservative all-standard-UK assumption; only Scenario four reflects the 25% premium-UK mix typical for B2B. Fluxa is 1.8% flat regardless of card type - the same rate on consumer, business, corporate and prepaid cards.
• Stripe Tax for UK VAT calculation. Basic plan: 0.5% per transaction where you are registered to collect tax, or £70/month on a one-year Tax Complete contract. For Scenario 3 (£200k/month) the Basic rate works out at £1,000/month, taking the annual Stripe saving with Fluxa from £19,242 to over £31,000. For Scenario 4 (£500k/month) it is £2,500/month, taking the annual saving from £52,030 to over £82,000. Fluxa pulls VAT data from settlements and submits the return to HMRC via the MTD bridging API.
• Currency conversion (2%). If a US customer pays you in USD and you settle in GBP, Stripe adds 2% on top of the 3.25% + 20p non-EEA card rate, taking the effective rate to 5.25% + 20p. Fluxa settles in GBP only and charges 1.8% flat regardless of card origin.
• Multi-currency settlement (1%). If you hold balances in USD or EUR rather than settling in GBP, Stripe charges 1% of settlement volume. Fluxa is GBP-only by design and has no equivalent fee.
• Instant settlements (1%). Stripe charges 1% of settlement volume (minimum 40p) for settlements that arrive within minutes. Fluxa aims to settle T+1 from the payments partner to your UK bank, with no surcharge.
• Stripe Chargeback Protection (0.4%). Optional add-on across protected transactions, capped at £20,000 reimbursement annually and excludes "product not received" and "not as described" disputes. Fluxa includes pre-dispute alerts and Tom-drafted representment in the 1.8% flat rate with no annual cap.
• Stripe Revenue Recognition. £20/month monthly subscription or from £150/month on a one-year contract. Needed for SaaS finance teams managing ASC 606 / IFRS 15 deferred revenue. Fluxa exports the underlying data from the double-entry ledger; the recognition logic lives in your accounting tool.
• Authorisation Boost on Stripe Custom (0.2%). If your monthly volume gets you onto Stripe Custom pricing, the network tokens, card account updater and Adaptive Acceptance bundle costs 0.2% per successful transaction. On £200k/month that is another £400/month. Free on Standard pricing.

Add any two of these and the scenarios above understate the Fluxa saving meaningfully. The point is not that every merchant pays every fee, but that Fluxa publishes one rate and Stripe’s real cost is a stack.

Where Stripe is the right choice

Two honest profiles where Stripe genuinely fits better than Fluxa, by design rather than by price:

• You need global card processing. Customers paying you from outside the UK with multi-currency settlement, local processing rate optimisation across Stripe’s 195-country footprint, FX management across 135+ currencies. Fluxa is UK-only by design and settles only in GBP.
• You need a marketplace or platform today. Multi-party splits, connected accounts, escrow flows, seller settlements. Stripe Connect (or Ryft or Mangopay) handles this category in production today. Fluxa Platform is on the roadmap but not generally available - if you cannot wait, Stripe is the right tool.

Custom pricing for high-volume merchants

The 1.8% above is the published standard rate. For merchants processing above roughly £500,000 per month, or with a high-ticket profile (average transaction above £500) where the standard flat rate is not the best fit, Fluxa offers custom pricing tailored to volume, card mix and risk profile. Same flat-rate structure, same included features, lower headline. Email apply@fluxapay.co.uk with your current monthly volume and average transaction size; you will get a custom rate from a founder within one working day.

For smaller merchants on Stripe Standard processing under £10k a month with no add-ons and clean disputes, the savings on Fluxa are real but modest. Honest answer: if you are happy on Stripe and the switching effort is not worth a small monthly difference, stay where you are. Fluxa is most worth switching to when one or more of the add-ons in the table below are part of your stack.

Scenario assumptions: international card mix split into EEA (2.5% + 20p) and non-EEA (3.25% + 20p) tiers as published by Stripe. UK SaaS card mix percentages drawn from Worldpay UK processing data and the British Retail Consortium. Stripe pricing as published on stripe.com/gb/pricing on 19 May 2026: 1.5% + 20p standard UK cards, 1.9% + 20p premium UK cards, 2.5% + 20p EEA cards, 3.25% + 20p non-EEA international cards. Radar for Fraud Teams 2p per transaction on Standard payments pricing; Stripe Sigma £11/month flat on the monthly subscription. Fluxa pricing is the published 1.8% flat standard rate; custom pricing is available for high-volume or high-ticket merchants on request.

Included as standard.

The headline rate is one number. The real cost of payments is what you pay across the year, including every add-on the rest of the industry charges separately for. Fluxa publishes one number and includes the rest. Two dozen things Stripe and others sell as paid add-ons or premium features, included in 1.8%.

Stripe add-on pricing verified May 2026 from stripe.com/gb/pricing (UK live page), including stripe.com/gb/radar/pricing, stripe.com/gb/sigma/pricing, stripe.com/gb/identity/pricing, stripe.com/gb/billing/pricing and stripe.com/gb/invoicing/pricing. Rates change. Specific add-on fees may differ on Stripe Custom plans negotiated above £80k monthly volume; the comparison above reflects standard published rate-card pricing.

Versus Stripe.

Stripe is the default UK choice for a reason. It is well-built, well-documented, and globally capable in a way Fluxa is not trying to be. The honest case for and against switching.

Where Stripe wins

• Global reach. 195 countries, 135+ currencies, 100+ payment methods. If you take payments outside the UK regularly, Stripe is the right tool. Fluxa is UK-only by design.
• Marketplace and platform support today. Stripe Connect handles multi-party payments, split commissions, seller onboarding and KYC for connected accounts and is the default choice for marketplaces live in production right now. Fluxa Platform - our Connect equivalent - is on the published roadmap, but not generally available today. If you need to launch a marketplace this quarter, stay on Stripe.
• Developer ecosystem. Decades of SDKs, plugins, community examples, ecosystem integrations. Fluxa publishes an API and one SDK; Stripe has thirty.
• High-ticket transactions on Stripe Standard. On UK-only transactions of £500 or more with no international cards and no disputes, Stripe’s 1.5% + 20p effective rate falls to 1.54% (at £500), 1.52% (at £1,000) and approaches 1.50% on larger transactions, versus the published Fluxa 1.8%. Custom pricing is available from Fluxa for high-ticket or high-volume profiles; if you do not want to ask, Stripe is the simpler option.
• Brand recognition for raising capital. If you are pitching investors who like to see Stripe on the slide, that brand recognition is a real consideration.

Where Fluxa wins

• No per-transaction fee, no Fluxa dispute fee. On transactions under £67, Fluxa is cheaper because we do not charge the 20p that Stripe does. Sub-£10 SaaS-style transactions are dramatically cheaper on Fluxa: a £5 transaction costs Stripe 27.5p (5.5% effective) versus Fluxa 9p (1.8%). Disputes carry no Fluxa fee, where Stripe charges £20 per dispute received with another £20 if you submit evidence (the submission fee is refunded only if you win; the original £20 is retained regardless).
• Predictable flat rate. What you pay this month is what you paid last month is what you will pay next year. Stripe’s effective rate moves with international mix, dispute rate, instant-settlement usage and scheme-fee passthrough.
• UK-native, GBP-native. Built for UK businesses, on UK rails, settling in GBP only. No currency conversion games, no cross-border interpretation, no platform decision tree.
• Named human support. Support is answered directly by the Fluxa team, not a chatbot or an outsourced first line. There is no 24/7 phone desk; a named human replies within one working day.
• No surprise account freezes. Fluxa publishes its acceptable-use policy in advance and documents every account decision in writing with named human review. Where a Fluxa-merchant disagreement happens, the route to a real conversation is published on the complaints page.
• Full state visibility. Every payment on Fluxa progresses through six explicit states (received, captured, settling, settled, plus failed and refunded as terminals) visible in real time. Stripe’s dashboard shows transaction statuses (succeeded, pending, failed, uncaptured, refunded, disputed) but does not expose the settlement phase between “succeeded” and the money arriving in your bank account.

Honest verdict

If you ship globally or operate a marketplace, stay on Stripe. If you take UK-domestic card payments, predominantly low-to-mid-ticket, and the unpredictable monthly bill from Stripe’s extras is something you would rather not budget around, Fluxa is the cheaper and quieter choice.

Versus Adyen.

Adyen is built for enterprise. Transparent Interchange++ pricing, global card processing, sophisticated risk tooling. Whether it is right for you depends almost entirely on monthly processing volume.

Where Adyen wins

• True interchange transparency. Adyen passes through the actual scheme interchange plus a flat markup. For a finance team that wants to see every penny of cost itemised, that is the gold standard.
• Enterprise-scale infrastructure. Single platform across online, in-store, recurring, settlements, and risk. Built for tens of millions of transactions monthly.
• Global processing depth. Local processing in more markets than almost any rival, which lifts authorisation rates significantly for international card volume.

Where Fluxa wins

• No volume floor. Adyen does not publish a hard minimum, but the commercial reality is they target enterprise scale; integrations are sold by a sales team and typically commercial sense kicks in around £50,000+ monthly processing. Fluxa has no minimum.
• Predictable flat rate. Adyen’s Interchange++ means your bill genuinely changes month to month with consumer card mix. For most SMEs that volatility is an operational tax, not a benefit.
• Onboarding in days, not months. Adyen integration is a serious engineering project. Fluxa onboarding is built for a founder doing it themselves in a working week.

Honest verdict

If your monthly card volume is above £500,000 and you have a finance team, look at Adyen seriously. Below that, the operational overhead of Interchange++ pricing outweighs the marginal cost saving. Fluxa is built for the band Adyen explicitly does not target.

Versus Square.

Fluxa is online checkouts only; it has no card reader, no terminal, no in-person product. The honest comparison is online-versus-online: Square’s eCommerce API and Square Online versus Fluxa. Square’s reader business is a different product for a different audience and is not in scope here.

Square online UK pricing (May 2026)

Square charges 1.4% + 25p for UK cards and 2.5% + 25p for non-UK cards across its online checkout products: Square eCommerce API, Square Checkout Links, Square Online and digital gift card purchases. Manually-keyed payments through Virtual Terminal, Square Invoices and card-on-file are at a separate 2.5% rate (with the same 1.5% surcharge on non-UK cards). There is no monthly fee for the API itself. Square Online (the website builder) has paid tiers in the UK: Plus £20/month adds a custom domain and the Subscriptions feature; Premium £64/month drops the per-transaction fixed fee from 25p to 15p. For Subscriptions, the rate depends on the channel: signups via Online Checkout are at 1.4% + 25p, but recurring auto-renewals charged to a stored card on file fall under the 2.5% manually-keyed rate. Square does not charge a chargeback fee and includes dispute representment; refunds do not return the original processing fee.

Where Square Online wins

• Mid-to-high-ticket UK domestic cards. On a UK domestic transaction above roughly £63, Square’s 1.4% + 25p is cheaper than Fluxa’s 1.8% flat. At £100 it is £1.65 versus £1.80; at £500 it is £7.25 versus £9.00. If your business is exclusively UK domestic with mid-to-high-ticket transactions, Square has the cheaper headline.
• Sole trader and micro-business onboarding. Sign-up to first transaction in under an hour, no UK limited company structure required. Fluxa onboarding is built for a Companies House registered entity with a UK bank account and is heavier by design.
• Ecosystem of plug-and-play integrations. WooCommerce, BigCommerce, Wix and WordPress all have first-party Square connectors. Fluxa is a direct integration only; it has no marketplace of pre-built connectors.

Where Fluxa wins

• Non-UK card payments. Square charges 2.5% + 25p for cards issued outside the UK. Fluxa is 1.8% flat on every card. On a £100 transaction from a US customer, Square is £2.75 versus Fluxa’s £1.80; Square is 53% more expensive than Fluxa on the same transaction.
• Subscription renewals from a card on file. Once a SaaS customer signs up, every monthly renewal charged to the stored card on file is at Square’s manually-keyed rate of 2.5%, not the 1.4% + 25p online checkout headline. On a £100/month subscription, that is £2.50 per renewal on Square versus £1.80 on Fluxa. Fluxa is 28% cheaper on every renewal. Over a year of 500 active £100 subscribers, that is £4,200 in saved Square fees.
• Low-ticket online transactions. Below roughly £63 per transaction, Fluxa’s no-per-transaction-fee model beats Square’s 1.4% + 25p. At £20 it is £0.36 on Fluxa versus £0.53 on Square. Sub-£10 transactions are dramatically cheaper on Fluxa: a £5 charge is 9p on Fluxa versus 32p on Square.
• Refund handling. Fluxa returns the original processing fee on refunds, pro-rata on partials. Square does not return processing fees on refunds. For a business with even a 2% refund rate, the difference compounds across the year.
• UK-specific compliance and tooling. MTD VAT submission to HMRC via the bridging API, KYB via Companies House lookup, beneficial-owner identification, sanctions and PEP screening built into onboarding, hash-chained audit trail, FCA-payments partner relationship documented in writing. Square is competent globally but not UK-tailored at this depth; HMRC integration would need a third-party tool.
• UK PSR APP fraud cover. Fluxa tracks the five-day window, manages the 50/50 bank-split evidence pack and maintains audit-ready records for the UK PSR regime that came into force October 2024. This is not part of Square’s product.
• Pre-dispute alerts and AI rebuttal drafting. Fluxa includes Verifi (Visa) and Ethoca (Mastercard) pre-dispute alerts that fire 24-72 hours before a chargeback so you can refund first and avoid the dispute. Tom drafts the rebuttal end-to-end if a chargeback proceeds, with evidence pre-pulled. Square handles disputes but does not include pre-dispute network alerts or AI-drafted representment.
• Six-state settlement visibility and double-entry ledger. Every payment is visible across PAYMENT_RECEIVED, CAPTURED, SETTLING, SETTLED and the two terminal states. Fluxa publishes a double-entry ledger with row-level fee breakdown and a SHA-256 hash-chained audit trail. Square’s dashboard is solid for typical merchants but does not expose this depth.
• AI workforce. Tom, the operations agent, handles daily briefings, decisions log, inline ask-Tom on any number, autonomy dial per task type. Square does not have an AI workforce layer.

Honest verdict

If your online business is UK-only, mid-to-high-ticket one-off transactions, and Square’s included online tooling fits your needs (basic subscriptions, basic invoicing, standard dispute handling), Square’s 1.4% + 25p edges Fluxa on headline rate above £63 per transaction. For SaaS with recurring subscriptions billed to a card on file, Square’s renewal rate of 2.5% is meaningfully more expensive than Fluxa’s 1.8% on every single renewal. And for every other online profile - international customers, low-ticket transactions, UK-specific compliance (MTD VAT, APP fraud, KYB), advanced dispute handling, the AI workforce layer - Fluxa is the more capable choice and often cheaper too.

Versus GoCardless.

GoCardless is a recurring-payments specialist using UK Direct Debit, not a card processor. The comparison is less about features and more about which payment method your customers can pay with.

Where GoCardless wins

• Recurring-billing cost. 1% + 20p per transaction, capped at £4, for UK Direct Debit on the Standard plan. For a £1,000 monthly subscription, that is £4 (the cap) versus Fluxa’s £18 at 1.8%. For a £100 transaction, that is £1.20 on GoCardless versus £1.80 on Fluxa.
• No card data ever. Direct Debit means no PCI scope, no card-on-file expiry handling, no failed-renewal recovery from expired cards.
• Trusted by enterprise finance teams. Direct Debit is how most UK utility, insurance and subscription billing moves.

Where Fluxa wins

• Card acceptance. Most consumer-facing UK businesses cannot ask every customer to set up a Direct Debit mandate. They need Visa, Mastercard, Apple Pay and Google Pay support, which is what Fluxa does.
• Instant authorisation. A Fluxa card payment confirms in seconds. A Direct Debit takes 2 to 5 working days to clear and can fail silently for weeks if the mandate is broken.
• One-off payments. Direct Debit is built for recurring. GoCardless can do one-off pay-ins but the customer flow is awkward. Card payments via Fluxa are the right tool for any one-off transaction.

Honest verdict

If your entire revenue is monthly recurring subscriptions and your customers are happy to give you a Direct Debit mandate, GoCardless is cheaper and more reliable for that one job. For everything else, including card-based subscriptions, you need a card processor and Fluxa is the cheaper UK-native option versus Stripe at typical SME volumes.

Who Fluxa is right for.

The honest profile of a business Fluxa is built for. If three or four of these descriptions match yours, you are in the ICP.

• UK-domiciled. Companies House registered in England, Wales, Scotland or Northern Ireland. UK bank account, UK customers, GBP settlement.
• B2B SaaS or digital product. Software, services, content, training, professional services, online media. Predictable transaction sizes, near-zero refund rate, low dispute rate.
• Monthly card volume from £5,000 upwards. Big enough that the per-transaction 20p on Stripe adds up. The published 1.8% rate applies up to roughly £500,000 per month; above that, custom pricing is available, tailored to volume and card mix.
• Average transaction below £500. Below this point the flat 1.8% beats Stripe’s 1.5% + 20p once disputes and the occasional international card are factored in.
• Wants predictable pricing. Hates the surprise of a monthly bill that moves by 15% with consumer card mix or international purchases.
• Cares about UK data residency. Customer data, transaction logs and operator activity all stored in UK infrastructure.
• Wants a named human at the other end. The named people on the About page are the same ones who answer support emails. There is no first-line tier.

Who Fluxa is not right for.

If three or four of these descriptions match your business, do not switch to Fluxa. We would rather you knew now than after onboarding.

• You take payments outside the UK regularly. Fluxa is UK-only. If more than a quarter of your card volume comes from international cards, Stripe is genuinely the better tool.
• You need to run a marketplace or platform today. Multi-party splits, connected accounts, escrow flows, seller settlements. Fluxa Platform is on our roadmap, but not generally available today. If your launch is this quarter, look at Stripe Connect, Ryft or Mangopay. If your launch is later in the year, talk to us about early access.
• Your business is primarily in-person. Fluxa is online checkouts only and does not sell card readers, terminals or any card-present hardware. For above-counter retail, hospitality, market stalls or mobile services you need a hardware-first provider such as Square, SumUp or Zettle. This is a scope limit rather than a price comparison.
• You need Amex acceptance. Fluxa does not currently process American Express. Visa, Mastercard, Apple Pay and Google Pay only at launch.
• You need crypto onramps, gambling, adult content, or any category on the acceptable-use restricted list. See the acceptable use page for the full list and the reasoning.
• Your revenue is exclusively recurring Direct Debit. Use GoCardless. The card-payment overhead is not worth carrying.
• You need PSD2-licensed marketplace authorisation in your own name. Fluxa operates as a Referrer to an FCA-authorised payments partner. If you need to be the regulated entity yourself, work directly with an FCA Authorised Payment Institution.

Switching to Fluxa.

If you have read this far and the fit looks right, this is what moving to Fluxa looks like. No migration marketing fluff; the real steps.

1. Apply via the founder inbox. One email to apply@fluxapay.co.uk describing your business, monthly volume, average transaction, refund rate and current provider. Read by a founder, not a CRM.
2. Verified Commercial Identity (VCI). Fluxa runs a Companies House lookup, beneficial-owner identification, sanctions screening and the underwriting documentation our payments partner requires. Typically completes within one to three working days for a UK Ltd with clean records.
3. Sandbox integration. Hosted checkout (pay.fluxapay.co.uk) needs zero code; the embedded SDK is a single <script> tag and an init call. Webhooks are signed with HMAC-SHA256 on X-Signature; idempotency keys on every write.
4. Test transactions. Sandbox cards exercise every state in the six-state machine. Refund flow, dispute flow, recurring renewal flow, all testable end to end before any live card touches the platform.
5. Go live. Switch the publishable key. Fluxa settles directly from the payments partner to your UK bank account in GBP, with T+1 the aim. No platform-held balance.
6. Parallel run, if you want one. Most merchants prefer to point a percentage of traffic at Fluxa for the first month while keeping the existing provider live. This is supported and encouraged. No volume commitment, no exclusivity clause.

No setup fee. No monthly minimum. No exclusivity clause. Flat 1.8% on every card (UK, EEA, non-EEA international, all the same), no per-transaction fee, no scheme-fee passthrough. Statement-format export available on day one if your accountant needs it.