Hosting a B2B SaaS in the EU: AWS vs OVH cost in Dublin (2026)

The verdict in three sentences

For an EU startup, whether in Dublin or Nice, selling to local authorities, hospitals or public bodies, a qualified European host (OVHcloud or Scaleway) removes the most common legal objection: exposure to the US CLOUD Act. AWS (Paris or Ireland region) remains faster to build on thanks to its managed services, but costs on average 30 to 60% more at launch and does not solve the extraterritoriality question. The right choice depends less on the monthly bill than on your target portfolio and the exit cost if you have to migrate in two years.

What public sector clients actually require in 2026

European public buyers and large accounts now write precise clauses into their tenders. The most common: data stored and processed in the European Union, listed sub-processors, no exposure to an extraterritorial law, and for health data in France, an HDS-certified host. The most sensitive contracts (health, defence, sovereign data) target the French SecNumCloud qualification from ANSSI.

For a B2B SaaS sold to private SMEs, AWS usually passes security questionnaires without difficulty. As soon as the target includes public buyers or health data, a European host becomes a sales argument, or even an eligibility condition.

What a B2B SaaS infrastructure costs at launch

The 2026 estimates below match a SaaS with 20 to 200 B2B customers: one web application, a managed PostgreSQL database, object storage, a staging environment and monitoring.

The most underestimated item is outbound bandwidth: AWS charges for data egress beyond a free threshold, while OVHcloud includes it generously. For a SaaS that generates exports, PDFs or heavy files, the gap can reach EUR 100 to 400 per month at equal volume.

Exit cost, disaster recovery and development speed

The monthly price is only part of the equation. Three hidden costs weigh more heavily on a growing startup.

Exit cost. The more proprietary services you use (DynamoDB, Lambda, Cognito), the more expensive a migration to a European host becomes. A containerised architecture (Docker, Kubernetes) with standard PostgreSQL migrates in 10 to 25 working days. An architecture tightly coupled to AWS services can require 40 to 80 days, or EUR 25,000 to 60,000 excl. VAT of development.

Disaster recovery. Public clients ask for an RPO (maximum data loss) and an RTO (maximum downtime) written into the contract. Targeting a 24-hour RPO and a 4-hour RTO costs EUR 50 to 150 per month. Going down to a one-hour RPO with failover to a second region climbs to EUR 200 to 300.

Development speed. AWS saves time on advanced building blocks: message queues, search, AI, authentication. On OVHcloud or Scaleway, the team installs more components itself, which means 5 to 15 extra working days on an MVP. Scaleway has narrowed this gap considerably with its serverless offers and managed databases.

Mini case study

Léa, CTO of a startup in Nice that publishes booking software for sports facilities, has just signed two inter-municipal authorities. Their DPO requires hosting in France by a company not subject to the CLOUD Act.

Current setup on AWS Paris: EUR 720 per month of infrastructure and EUR 180 of backups, i.e. EUR 10,800 per year. Projection on Scaleway with an equivalent architecture: EUR 430 of infrastructure and EUR 120 of disaster recovery, i.e. EUR 6,600 per year. As the application is already containerised with standard PostgreSQL, the migration is estimated at 15 days, roughly EUR 9,000.

Calculation: 10,800 minus 6,600 gives EUR 4,200 of annual savings. The migration pays for itself in just over two years, but the real gain lies elsewhere: the two public contracts represent EUR 38,000 of annual recurring revenue, and three other authorities are in a tender phase with the same requirement.

FAQ

Is a SaaS hosted on AWS in the EU GDPR compliant?

Yes, AWS offers an Article 28 compliant DPA and data located in EU regions. The friction point remains the CLOUD Act, which leads roughly one public buyer in two to favour a European host in its scoring criteria.

Should we target SecNumCloud from day one?

Rarely. SecNumCloud mainly concerns sensitive state, health and critical operator data in France. A qualified offer often costs 1.5 to 2 times a standard offer, so keep it for contracts that explicitly require it.

What budget should we plan for backups and disaster recovery?

Count EUR 50 to 300 per month depending on the target RPO. A daily encrypted backup on a separate site is enough for most B2B SaaS products with fewer than 200 customers.

Can we start on AWS and migrate later?

Yes, as long as you stay on standard building blocks: containers, PostgreSQL, S3-compatible storage. The migration then takes 10 to 25 days instead of 40 to 80 days.

Who writes the record of processing and the sub-processor list?

The SaaS publisher, as processor for its customers. Plan 3 to 5 days to produce a DPA, a sub-processor list and a security policy you can reuse in every tender.

Let's scope your project. We design or migrate your B2B SaaS onto a portable, compliant architecture, with a costed scope, a custom application budget (2.5M to 15M+ FCFA depending on complexity, about EUR 3,810 to 22,870+) and a schedule. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.