Building a marketplace: the complete 2026 guide
Building a marketplace means creating a platform where third-party sellers offer their products or services to buyers, in exchange for a commission or a subscription. The project comes down to three decisions: the revenue model, the technical solution and the payment setup. Collecting funds on behalf of sellers is a regulated payment service in France, reserved for licensed institutions. Obligations differ depending on whether buyers are consumers or businesses.
In 2025, 4.62% of French companies with ten or more employees sold through a marketplace, and those sales accounted for 10.24% of their web turnover. Most guides are written for someone starting from scratch to sell to the general public. An SME, a distributor or a network rarely starts from scratch: it already has suppliers, business customers and a catalogue.
This guide explains how to build a marketplace in 2026, in the order the decisions are made: the model, the technical solution, the payments. It sets out an operator’s obligations, read from the texts themselves, and distinguishes what applies when buyers are consumers from what applies when they are businesses.
🧩 What is a marketplace?
A marketplace is an online platform that connects third-party sellers with buyers and secures the transaction between them. The ACPR, France’s banking supervisor, describes it as a “trusted intermediary” that receives the buyer’s payment and passes it on to the seller of a good it does not sell itself. The operator owns neither the stock nor the service: it provides the infrastructure, the audience and the framework, and earns money on each exchange or through a subscription.
The French Consumer Code defines an “online marketplace” as a service “which allows consumers to conclude distance contracts with other traders or consumers”. A platform reserved for business buyers falls outside that definition, and its obligations are different.
Marketplace, e-commerce site, matchmaking portal: three different things
Three models look alike on screen and differ in how the money flows.
A matchmaking service that collects no funds remains an ordinary custom web application, outside the payment framework.
How a marketplace makes money
Four revenue models are found, often combined. In every case, the platform’s remuneration is a supply of services subject to VAT at 20%, reverse-charged by a seller established in another Member State.
Products, services, B2C, B2B: what changes when both sides are businesses
Between businesses, a marketplace does not sell at the price displayed to everyone. Prices are negotiated per account, orders go through quotes and an approval workflow on the buyer’s side, and payment comes after delivery. The French Commercial Code sets that term at 30 days by default and caps it at 60 days from the invoice, or 45 days end of month. Every order gives rise to a mandatory invoice.
These rules become features: multi-user accounts, price lists per customer, quotes, deferred payment, connection to sales management. Building a B2B marketplace therefore looks more like custom business software than an online store.
🧭 Who is concerned, and when is it the right answer?
Building a marketplace concerns two profiles: the founder who starts from scratch and must convince two audiences at once, and the established company that already has one of the two. Official figures call for caution. In France, 1.07% of companies with ten or more employees sell only through a marketplace, and the share of those selling through one went from 5.63% in 2017 to 4.62% in 2025.
Starting from scratch: the chicken and the egg
Without sellers, no buyer comes; without buyers, no seller signs up. The founder chooses which side to recruit first and delivers value to it before the platform even exists. It is the best-documented case, and the riskiest: everything has to be acquired.
An established company: distributor, network, buying group
A distributor has suppliers and business customers. A franchise network or a buying group has members who already place orders. In each of these cases, one side exists: the marketplace opens the other, or replaces an ordering process run by phone, email and spreadsheet. The start is easier, the specification heavier: negotiated prices, payment terms and catalogue data all have to be carried over.
When not to build a marketplace
A marketplace is only the right answer if third parties sell, and if the platform secures the exchange between them. In other cases, a custom web application meets the need with fewer constraints.
Third parties sell in their own name, and you want neither to buy nor to stock their products.
Both sides need a shared framework: catalogue, ordering, secure payment, disputes.
You already have one of the two sides, suppliers or business customers, and an ordering process to replace.
You accept the role of operator, with its payment, information and reporting obligations.
You buy to resell: that is multi-supplier B2B e-commerce, you collect payment for yourself, outside the regulated framework.
You want an ordering and tracking space for your partners: a portal or an extranet is enough.
You connect parties without collecting funds: a matchmaking application, with no payment provider.
⚖️ A marketplace operator’s obligations in 2026
A marketplace operator carries three families of obligations: on payments, on user information and seller traceability, and on tax. The first applies as soon as the platform collects funds. The other two depend on who buys: the French Consumer Code, DSA seller traceability and the P2B Regulation target platforms open to consumers; between businesses, the Commercial Code and e-invoicing take over.
Collecting funds on behalf of sellers is a regulated payment service
Receiving buyers’ money and then passing it on to sellers falls under the payment services defined in article L. 314-1 of the French Monetary and Financial Code. Article L. 521-2 reserves them, as a regular business activity, for licensed providers: payment institutions, electronic money institutions or credit institutions. Operating without a licence is punishable by three years’ imprisonment and a €375,000 fine.
Three routes keep you within the framework.
An exemption exists for a limited network of acceptors or a limited range of goods or services. The ACPR has granted it to thematic marketplaces (pharmacy products, wine, farm produce, ticketing), but rules it out for any “universal” offering or for a network “intended to grow”. Above one million euros of flows over twelve months, the exempted company must file a declaration with the ACPR. Provider prices are given in the cost section.
User information, seller traceability: what applies in B2C and in B2B
A marketplace’s information duties are owed to the consumer, and several texts quoted everywhere target the consumer alone. The table lists each obligation with the text currently in force.
Two clarifications. French law does not require the platform to verify that a seller is a private individual: it displays the “declared” status, and a false declaration is a misleading practice on the seller’s part. And the definition of the “online platform operator”, still quoted by many guides, was repealed in 2024.
VAT, DAC7 and e-invoicing
Three tax mechanisms target platforms.
Joint liability for a seller’s VAT. Since 1 January 2020, article 283 bis of the French General Tax Code allows the platform to be held jointly liable for the VAT owed by a defaulting seller, after notification by the tax authority, one month to act, a formal notice and a further month. It targets any VAT-registered seller, whatever its country, for sales to private individuals taxable in France. Since 1 July 2021, the platform is also deemed to be the seller itself for imported goods worth less than €150 and for sales to private individuals by a seller established outside the EU. A marketplace between EU businesses is concerned by neither.
The DAC7 report. Every operator reports to the tax authority, by 31 January at the latest, the sellers active on its platform in the previous year and their income, private individuals and businesses alike, and gives each of them a copy. There is a single exclusion: fewer than thirty sales of goods for less than €2,000; a service provider is reported from its first transaction. The fine is capped at €50,000. The platform must also inform each seller, at every transaction, of its tax and social obligations.
E-invoicing between businesses. Since 1 September 2026, every company established in France must be able to receive electronic invoices; large companies and mid-caps have been issuing them since the same date, SMEs and micro-enterprises from 1 September 2027. Invoices pass through an accredited platform; outside that circuit, the fine is €50 per invoice, capped at €15,000 per year. On a B2B marketplace, each seller remains the issuer of its own invoices; the platform can issue them on its behalf under an invoicing mandate, concluded before the first invoice, with the seller remaining liable for the VAT.
One calendar note: on 1 January 2027, the VAT rules move from the General Tax Code to the Code on taxes on goods and services. The rules stay the same; the article numbers change.
🧰 What to gather before you start
Building a marketplace means gathering, before the software, what the platform will have to apply: the side you already have, the catalogue, the commercial rules and the ordering process. The vendor or the software publisher provides the scope of the first launch, the payment setup and the exit terms.
What you prepare in-house
- The side you already have, and its contracts. Supplier or customer files, negotiated terms, volumes. They will come if the platform simplifies a task they already perform, not because they know you.
- The catalogue and its data. References, descriptions, prices, availability, in a form software can use. A catalogue in PDFs and mismatched spreadsheets is the first hidden workload.
- The commercial rules. Who sets prices, what discounts, what payment terms, who delivers, who handles a dispute. These rules, not the screens, make the marketplace.
- The current ordering process. How an order arrives, who approves it, how it is invoiced: the platform must do at least as well from day one.
- The person who will run the platform. Recruiting sellers, answering buyers, administering: that work exists even on a subscription.
- The tax constraints identified. Your sellers’ status, whether you sell to private individuals, your entry date into e-invoicing.
These elements feed the software specification, as described in the complete guide to custom software development.
What the vendor or the software publisher must provide
- The scope of the first launch, in writing, with what is not part of it.
- The chosen payment provider and the split of roles: who collects the sellers’ identity documents, who controls the funds, who signs with the provider.
- Connections to your existing systems: sales management, invoicing software, accredited e-invoicing platform.
- Ownership of the code or the exit terms: on a subscription, how to retrieve data and sellers; on a custom build, who owns the code.
- The scaling plan: what happens beyond the first tier of sellers or transactions.
🛠️ Building a marketplace step by step
Building a marketplace follows six steps: validate demand, set the model and the rules, choose the solution, scope the first launch, connect payments and compliance, recruit the first side. No independent source measures how long each one takes; the only published timelines are vendor promises. What takes time is rarely the software.
A realistic timeline
Step 1: validate demand before building
The first step requires no software. Connecting a few sellers and a few buyers by email or in a spreadsheet lets you check that both sides have a need, and which one: what buyers look for first, what commission sellers accept, where the current process gets stuck. An established company has a shortcut: its existing orders already say what is bought, how often and on what terms.
Step 2: set the model and the rules
The revenue model is decided before the technical solution, because it determines it. A commission means the platform collects funds, hence a licensed payment provider; a subscription or pay-per-lead model can do without one. The rules are written next: who sets prices, who delivers, who handles disputes, what happens when a seller stops responding. In B2B, add payment terms and the approval workflow on the buyer’s side.
Step 3: choose the solution, subscription, open source, no-code or custom build
Four families of solutions exist for marketplace development. Prices are those on official pages as of 16 September 2026; vendors that do not publish any are flagged.
No-code sits between the two: tools such as Bubble or Airtable can build a simple matchmaking service, at the price of limited scalability. The general trade-off between no-code and custom development applies here, as does the one between custom SaaS and an off-the-shelf solution.
Step 4: scope the first launch and its features
The first launch contains what a transaction cannot happen without, and nothing else: seller and buyer accounts, a catalogue managed by sellers, search, cart, payment, order tracking, messaging, a dashboard with commission calculation. Reviews, multi-seller carts and dispute management come later.
In B2B, four features change the nature of the project: multi-user accounts with order approval, prices per customer, quotes, deferred payment connected to sales management. They cannot be configured in consumer-grade software: that is where a subscription stops being a shortcut.
On your own, this scoping is done with the specification and the rules gathered above. At OTTOPILOTE, the initial brief takes a few sentences on the get started page, the quote arrives within 24 working hours, and scoping takes up the first week of the project, included, with the quote signed before the first line of code.
Step 5: connect payments and compliance
The contract with the payment provider is the critical piece of the project: it sets who controls the funds, hence whether the platform must become an agent, and who collects the sellers’ identity documents. Then come the documents: terms of use for each side, the platform’s terms of sale, privacy policy, legal notice. In B2C, add the information owed to consumers, seller traceability and the fifteen days’ notice; in B2B, the accredited e-invoicing platform and, where relevant, the invoicing mandate.
Step 6: recruit the first side and launch
A marketplace launches with a few chosen sellers, not with an exhaustive catalogue. An established company starts with the partners who already order from it, and gives them a reason to go through the platform: an up-to-date catalogue, order tracking, an invoice without having to ask. The launch is gradual, with invited buyers and real orders; what gets measured next is the share of orders placed on the platform rather than through the old process.
💶 How much does it cost to build a marketplace?
Building a marketplace has no single price, and no independent source quantifies a complete project: the ranges in circulation come from marketplace software vendors, with no published method, and contradict each other from one page to the next. What can be priced are the line items, with the public prices of the tools and the one that is never included: the time spent recruiting and animating.
The budget by line item
The cost over time: subscription and publisher commission, or owned code
The price of a subscription grows with activity: plans are capped in transactions, sellers or listings, and extra capacity is paid for, $0.19 per transaction beyond the quota at Sharetribe, €49 per thousand units at Kreezalid. Exit terms, data and sellers included, are read before signing: vendor lock-in is decided on day one.
A custom marketplace costs more up front and does not charge for volume. At OTTOPILOTE, the source code is transferred to the client on delivery, once the project is paid, along with access credentials and documentation. The custom SaaS price estimator gives an order of magnitude by scope.
⚠️ The most common pitfalls
Five pitfalls recur in marketplace projects, and none of them is about code: they come from the texts, from payments and from what precedes the software.
Five pitfalls, and how to avoid them
Receiving buyers' money on your own account to pass it on later is an unlicensed payment service: three years' imprisonment and a €375,000 fine.
Fix A licensed provider from the very first transaction.
A B2B platform that imposes DSA traceability on itself works for nothing; a platform open to private individuals without having planned for it faces a fine of up to €375,000.
Fix Decide who buys, and write it into the terms.
References in PDFs, prices in different spreadsheets, missing photos. The platform is ready, the catalogue is not, and the sellers will not key it in.
Fix The data format set at scoping, a sample loaded at acceptance testing.
A commission that eats a seller's margin makes it leave or bypass the platform, and the payment provider's fees come on top at every transaction.
Fix Test the commission with the first sellers, before coding it.
Each seller's identity, tax residence and income must be reported before 31 January. If not collected at sign-up, they have to be chased in a hurry, under threat of a fine of up to €50,000.
Fix DAC7 data in the seller sign-up form.
🎯 In summary
The decision that governs all the others is not a technical one: it is knowing who will buy, consumers or businesses. It settles which texts apply, which features to plan for and which payment setup to negotiate, and it is taken before the first quote.
The order of the steps follows from it: test demand without software, write the rules of the game, have your setup qualified by the institution that will hold the funds, then choose the tool — never the other way round.
A successful marketplace is not the one with the most features: it is the one whose rules were written before the software, and whose payments were compliant from the very first order.
📚 Sources
- French Monetary and Financial Code, article L. 314-1 (Légifrance): definition of payment services and exclusions
- French Monetary and Financial Code, article L. 521-3 (Légifrance): licence exemption and declaration to the ACPR
- French Monetary and Financial Code, article L. 572-5 (Légifrance): penalty for unlicensed activity
- ACPR, “I collect funds and pass them on to a third party?” (in French): qualification of collecting funds on behalf of third parties, agents, the commercial agent exception
- ACPR, position 2022-P-01 on limited networks and limited ranges (in French): application of the exemption to marketplaces
- French Consumer Code, article L111-7 (Légifrance): information owed to consumers by an online marketplace provider
- Regulation (EU) 2022/2065, Digital Services Act (EUR-Lex): articles 11 to 16, 19, 29, 30 and 52
- Regulation (EU) 2019/1150, platform-to-business relations (EUR-Lex): scope and obligations
- French Commercial Code, article L441-10 (Légifrance): payment terms between businesses
- French General Tax Code, article 283 bis (Légifrance): the platform’s joint liability for VAT
- French General Tax Code, article 1649 ter C (Légifrance): sellers excluded from the DAC7 report
- BOFiP, BOI-INT-AEA-30-10 (in French): platform operators’ reporting (DAC7)
- Law No. 2022-1157, article 26 (Légifrance): e-invoicing timeline
- impots.gouv.fr, “From when am I concerned by the e-invoicing reform?” (in French): timeline by company size
- BOFiP, BOI-TVA-DECLA-30-20-10-30 (in French): invoicing mandate
- Eurostat, E-commerce statistics: business sales through marketplaces (datasets isoc_ec_eseln2 and isoc_ec_evaln2)
- Stripe, Connect pricing and Lemonway, pricing (in French): marketplace payment provider fees, recorded on 16 September 2026
- French General Tax Code, article 244 quater B (Légifrance) and Bpifrance, Bourse French Tech: innovation tax credit and grant
Frequently asked questions
Nobody can quote a single figure, and the ranges circulating online come from the very vendors selling the software. Build the budget line by line instead: the tool, the payment fees taken on every transaction, the contractual documents, and the one no published grid includes — the time someone spends recruiting sellers and answering buyers. That last line exists even when the software is rented by the month.
A marketplace starts with two sides to convince, sellers and buyers, where an online store has only one. The operator carries obligations a merchant does not: a licensed payment provider is mandatory if it collects funds for sellers, sellers must be reported under DAC7 every year before 31 January, and the platform can be held jointly liable for the VAT of a defaulting seller. It also depends on its software vendor or its payment provider, whose exit terms are negotiated before signing.
The software can be free; the project cannot. Multi-vendor extensions for WooCommerce such as Dokan Lite or WC Vendors exist in free versions, and open-source foundations such as Medusa or Saleor are under permissive licences. What still costs money: the payment provider, which takes a percentage of every transaction, hosting, contractual documents and the time spent recruiting the first sellers.
Rarely in its own name: a licence is the route of the large players, not of a launch. What decides your situation, the ACPR notes, is whether you can control the funds, and the contract you sign qualifies it. Three setups exist: your own licence, registration as an ACPR agent, or a payment specialist built for marketplaces. A limited network or catalogue can be exempt; past one million euros of flows over twelve months, it must be declared.
No independent source measures the time it takes to build a marketplace. Subscription software vendors advertise going live in a day to a few weeks, and set six to twelve months against custom development, without a published method. The real timeline depends mostly on what precedes the software: validating demand, the contract with the payment provider, recruiting the first sellers.
In B2C, buyers are consumers and the operator falls under the French Consumer Code, the seller traceability rules of the DSA and the P2B Regulation. In pure B2B, those texts do not apply, but the Commercial Code takes over: mandatory invoicing, general terms of sale to be provided on request, payment terms of 30 days by default and 60 days at most, and mandatory e-invoicing between businesses established in France.
Start by listing what your marketplace must do differently from everyone else's. If it all fits into configuration, a subscription is enough and puts you online without development. If it needs accounts with several approvers, prices negotiated per customer or a link into your management software — the common case between businesses — a custom build becomes the realistic route. Either way, look at what you take with you the day you leave.
On an e-commerce site, the company sells its own products and collects payment for itself. On a marketplace, third-party sellers sell, and the operator connects the parties, secures the transaction and earns a commission or a subscription. Collecting funds on behalf of sellers is what changes the framework: it becomes a regulated payment service, whereas a merchant freely collects its own sales.
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