Payment gateway for your website: Stripe, Redsys and Bizum

To collect payments on your website you have three main options in Spain: Stripe, the fastest and most flexible to integrate; Redsys, the gateway of the Spanish banks, often with lower fees; and Bizum, which many customers already use daily and which conveys instant trust. There is no best one in absolute terms: there is a best one for your case, and in this article I help you find it.

I am Elmar Mamedova, a full stack developer in Málaga, and I have integrated these three gateways into all kinds of stores and service websites. Here I tell you, no fluff, what each one offers, how much they really cost, how good the checkout experience is for your customer and in which situations I choose each. The goal is that you finish knowing which one (or which ones, because they can be combined) fits your business.

A payment gateway is the system that lets your website collect money securely: it takes the card details or authorises the payment through another method, validates it with the bank and deposits the amount to you. It is the bridge between your customer's «I want to buy» and the money in your account. Sensitive information passes through it, so security and trust are non-negotiable.

Choosing well matters for two very concrete reasons: money and conversion. Money, because each gateway charges a fee per sale and, over a year, that difference adds up. And conversion, because the payment moment is where most carts are abandoned: if the process is confusing, slow or does not offer the method your customer expected, you lose the sale on the finish line. A good gateway charges little and scares nobody off.

Stripe is the favourite of developers and digital businesses, and for good reason. Its integration is clean, its documentation is excellent and the payment experience it offers the customer is among the most polished out there: fast, modern and with secure card saving for future purchases. It supports cards, recurring payments (ideal for subscriptions) and international methods, which makes it perfect if you sell outside Spain.

Its fee is simple and transparent: a fixed percentage per transaction plus a small amount, with no setup fees or lock-in. In return, that fee tends to be slightly higher than a negotiated bank card terminal. For me, Stripe shines when flexibility and checkout experience matter more than squeezing out the last cent of fees: subscriptions, digital products, SaaS or any project that plans to grow and sell abroad.

Redsys is the platform behind the virtual card terminals of most Spanish banks (Santander, CaixaBank, BBVA and many more). Its big advantage is the fee: when you contract it through your bank, you can negotiate lower per-sale rates than Stripe, especially if you already have a commercial relationship with the entity and bill a decent volume. For stores with many sales, that difference translates into good annual savings.

The downside is that Redsys is more rigid. The integration is more technical and dated, the payment experience tends to be less elegant (it often redirects the customer to a bank screen) and it depends on dealings with your entity, which are not always quick. Even so, when the goal is to minimise fees and you already bill a volume that justifies it, Redsys is a very sensible option. I usually recommend it for established stores with frequent sales in the Spanish market.

Bizum has gone from being «the thing for paying a friend back for dinner» to an online payment method that millions of Spaniards use daily and trust blindly. That familiarity is its secret weapon: when a customer sees the Bizum button, they do not have to pull out a card or type long numbers, they pay from their phone in two taps with something they already know. That reduces abandonment and boosts conversion, especially on mobile purchases and with a Spanish audience.

Bizum is usually not your only gateway but a complement you add to Stripe or Redsys to offer more options. It integrates through Redsys or certain providers, and works wonderfully for small and medium amounts and for very local businesses. My usual recommendation is to offer Bizum alongside card: that way each customer pays however they feel most comfortable, and you capture sales that would slip away with a single method.

After all this, the decision is simpler than it seems if you ask yourself the right questions. It is not about which is «the best» in the abstract, but which fits how, to whom and how much you sell. This quick guide sums up what I usually recommend by profile.

• You sell subscriptions, digital products or abroad: Stripe, for its flexibility and international payment experience.
• You have an established store with many sales in Spain: Redsys through your bank, to lower fees.
• Your audience is Spanish and buys mostly on mobile: add Bizum without a doubt, alongside card.
• You are starting out and want to launch fast without complications: Stripe to get going, and you will optimise fees once you have volume.
• You sell services or collect one-off payments: Stripe or Bizum, depending on how international your customer is.

Whatever your case, the important thing is that the gateway is well integrated into your online store so payment is fast, secure and hassle-free. And do not forget that the gateway is only one part of the total cost of selling online; I break down the rest in how much an online store costs.

Before deciding, keep a couple of details in mind that make the difference. The first is security: all these gateways meet industry standards and apply the strong authentication required by European regulations, so your customer will confirm the payment with their bank. This protects against fraud but adds a step; a good integration makes it as smooth as possible so you do not lose sales along the way.

The second is real fees. The advertised figure is not always what you pay: you have to look at refund fees, international payment fees, currency conversion and, in the case of Redsys, possible terminal maintenance fees with your bank. Before signing anything, run the numbers with your real volume and average ticket. Sometimes the «cheapest» gateway turns out more expensive once you add up the fine print.

Stripe, Redsys and Bizum are not mutually exclusive rivals: they are pieces you combine based on who you sell to. Stripe wins on flexibility and experience, Redsys on fees for high volumes, and Bizum on trust and convenience for the Spanish customer. The best decision is almost never «one of the three» but the combination that gets your customer to pay without thinking twice.

My advice is to choose looking at your customer and your numbers, not at what is trendy. And to take care of the integration as much as the choice: the best-chosen gateway is useless if the payment process is slow or confusing. If you like, we can look at it together and set up the payment method that best fits your website, with no surprises in the fees.