How to handle EU VAT for SaaS as a founder

If you are a SaaS founder selling to EU customers, the short answer is: under €10,000/year in cross-border B2C revenue you can charge your home-country VAT rate and ignore the rest; above that, you must charge each customer their local VAT rate and file a quarterly OSS (One Stop Shop) return. For B2B sales to an EU business with a valid VAT number, you charge 0% under reverse charge. If you are based outside the EU, there is no threshold: VAT is owed from the first euro.

That is the whole compliance framework in 100 words. The rest of this post is how to actually do it without burning a month of engineering time, and when to pay someone else to make it disappear.

The two paths every founder picks between

There are really only two strategic choices. You either build VAT compliance into your billing stack, or you delegate it to a Merchant of Record (MoR) who becomes the legal seller and absorbs the entire problem.

Most founders do not realize they are picking between these two until they have already lost a week to it. So here is the trade-off table up front.

Approach	Cost	Setup time	Best for	Worst for
DIY with Stripe Tax	$0.50 per txn (0.5% of payment)	4-8 engineering days	EU-based founders past product-market fit; >€100k ARR	Pre-revenue, non-EU founders, anyone with <€500/mo to spend
DIY with Anrok / Sphere	~$149-499/mo + per-txn	2-3 engineering days	US-based SaaS scaling globally	Anyone under $5k MRR
Merchant of Record (Paddle, Lemon Squeezy, Polar)	5-7% of revenue + $0.50 per txn	A few hours	Pre-PMF founders, indie hackers, non-EU sellers, anyone who doesn't want to think about it	High-ARR companies where 5% is real money
Ignore it (B2B-only reverse charge)	$0 if true B2B	1 hour	Pure B2B SaaS with VAT-registered customers only	Anyone with B2C or mixed revenue

The honest framing is this: if you are doing under $20k MRR and selling globally, a Merchant of Record is almost always the right call. The 5% take is cheaper than the 30-40 hours of engineering time plus ongoing quarterly filings. Once you cross roughly $50k MRR and have stable EU revenue, the math flips and DIY with Stripe Tax or Anrok wins.

Where founders actually get stuck

The €10,000 threshold is the most-misread number in EU tax law.

Founders read it and assume "I am under €10k in EU revenue, I am fine." Wrong on two counts. First, it is only €10k in cross-border B2C sales. Domestic sales to your own country and all B2B sales are excluded from the count. Second, the moment you cross it mid-quarter, you owe destination-country VAT on every euro after the crossing, not from the next quarter.

If you are not based in the EU at all (US, UK post-Brexit, Canada, India, anywhere else), the €10,000 threshold does not apply to you. You owe EU VAT from the first transaction. The non-Union OSS scheme lets you register in one EU member state (Ireland and the Netherlands are common picks for English-language filing) and file quarterly for all 27 countries.

The other thing that catches founders: you need two pieces of non-contradictory location evidence per customer. Billing address alone is not enough. Common pairings are billing address + IP address, billing address + card-issuing country, or billing address + phone country code. Stripe captures most of this by default. If you are building checkout yourself, you have to store these explicitly.

The four numbers you actually need

Memorize these. Everything else is implementation detail.

• €10,000/year: EU-based cross-border B2C exemption. Below this, charge home rate.
• 17% to 27%: VAT rate range across 27 member states (Luxembourg lowest, Hungary highest).
• Quarterly: OSS filing cadence. Returns due by end of month after quarter close.
• 10 years: How long you must keep VAT records and customer location evidence.

That is the entire numerical foundation. Anyone who tells you it is more complex is selling you something.

What "B2B reverse charge" actually means in practice

B2B is the easy lane. If your customer is a business with a valid EU VAT number, you charge 0% VAT and put "reverse charge" on the invoice. The customer self-accounts for VAT in their country. You owe nothing.

The catch: you must validate the VAT number through the EU's VIES system before you trust it. Stripe Tax does this automatically. If you are rolling your own, hit the VIES SOAP endpoint (or one of the JSON wrappers) at checkout and store the validation response. An invalid VAT number means you must charge VAT, and getting this wrong means you eat the VAT yourself later.

The auditor's question is always: "show me the VIES validation logs for the customer who claimed B2B status three years ago." If you can produce a timestamped response, you are fine. If you cannot, you owe the VAT plus penalties.

This is the kind of compliance-shaped work that fits naturally into a one-week scoped booking. A mid-tier engineer on Cadence ($1,000 for the week) can ship Stripe Tax integration, VIES validation, location evidence storage, and a basic OSS export by Friday. The Cadence pool is at 12,800 engineers as of this week, and median time to first commit on a booking is 27 hours. Every engineer is AI-native by default, vetted on Cursor / Claude / Copilot fluency before they unlock bookings, so prompt-driven integration work moves faster than the typical contractor week.

The recommended path for most founders

Here is the default decision tree we would give a founder building a B2C SaaS today.

1. Under $5k MRR or pre-revenue: pick a Merchant of Record. Lemon Squeezy or Polar for indie scale, Paddle once you cross $10k MRR. The 5-7% take is cheaper than your time. You get checkout, fraud, refunds, dunning, and VAT for one price.

2. $5k-$50k MRR, EU-based, technical founder: integrate Stripe Tax. It is 0.5% of payment volume, no monthly fee, calculates VAT in 40+ countries, and produces OSS-ready reports. You still file the OSS return yourself (or pay an accountant €100-300 per quarter).

3. $5k-$50k MRR, non-EU, technical founder: Stripe Tax works too, but register for non-Union OSS first (Ireland portal is fastest, takes about two weeks). Pick your member state of identification carefully because you cannot easily change it later.

4. $50k+ MRR, mixed B2B/B2C, global: graduate to Anrok or Sphere. These are SaaS-native tax engines that handle US sales tax, EU VAT, UK VAT, Canadian GST/HST, and emerging digital service taxes in one stack. Pricing is around $499/mo base plus per-transaction.

5. Pure B2B with all-VAT-registered customers: validate VAT numbers via VIES, charge 0% with reverse charge, file nothing. This is the cheapest path and works perfectly if your ICP is mid-market and above.

Whichever path you pick, the actual setup work (Stripe Tax integration, VIES validation, evidence storage, customer-facing invoice generation, OSS export) is a one-week project for a mid-tier engineer. The decision-making takes longer than the implementation.

Common founder mistakes that cost real money

These are the ones we see again and again.

• Treating MRR as the threshold trigger. The €10k threshold is cross-border B2C, not total EU revenue. A French founder doing €50k/year domestically and €8k cross-border B2C is still under the threshold. Most founders count wrong and either register too early (extra work) or too late (back-VAT plus penalty).

• Skipping VIES validation on B2B claims. Customers will enter random strings as their VAT number to skip the 20% charge. If you do not validate at checkout and you accepted a fake VAT ID, you owe the VAT.

• Storing only billing address. The two-evidence rule is a hard requirement, not a suggestion. If you ever get audited, billing address plus a screenshot of the IP geolocation lookup is not enough. You need to have captured both at transaction time and stored them durably.

• Forgetting renewal events. Subscription renewals are separate VAT events. If a customer moves countries between subscription start and renewal, the renewal owes VAT at the new location's rate. Stripe Tax handles this; rolling your own usually misses it.

• Picking the wrong OSS member state. Once you register in (say) Germany, you file in German and your audit risk is in Germany. Most non-EU founders pick Ireland or the Netherlands for English-language filing and friendlier tax authorities. Talk to an accountant before registering.

When to skip building this yourself

The Cadence framing on tax compliance is simple: it is a solved problem with two good off-the-shelf answers (MoR for early-stage, Stripe Tax for past-PMF). You should not build a custom VAT calculation engine. You should not hand-roll OSS export logic. The juice is not worth the squeeze.

Where you do need a real engineer is the integration work: wiring Stripe Tax into your existing checkout, migrating from a homegrown billing flow to Paddle, building the admin dashboard your accountant needs to file the OSS return, and stress-testing edge cases like mid-subscription country changes.

This kind of one-week scoped backend work is exactly what weekly booking is built for. If you are deciding between hiring a full-time backend engineer for a 60-day loop or shipping VAT compliance this week, book your first engineer on Cadence for a 48-hour free trial. A mid-tier engineer ($1,000 for the week) ships the integration; if it is too small for that, a junior ($500/week) handles VIES validation and evidence storage in a few days.

If you are earlier and still figuring out whether you even need this, validate the marketplace idea before building and use a Merchant of Record until you hit product-market fit. Then revisit.

The shortest path to compliance: Use Stripe Tax (or a Merchant of Record) for the math. Use Cadence for the one-week integration. Use an accountant for the quarterly filing. Total cost: under $2,000 to fully solve EU VAT for the next year. That is the founder-friendly answer, and it ships by next Friday.

For founders thinking longer-term about engineering hires, the question of when to hire your first engineer usually comes up right around the same time as VAT. If you are scoping diligence for a fundraise, preparing for technical due diligence covers what investors want to see in your billing and tax stack.

FAQ

Do I need to charge EU VAT if I am based in the US?

Yes, from the first euro of revenue. The €10,000 cross-border threshold only applies to EU-established sellers. If you are a US, UK, Canadian, or other non-EU SaaS selling to EU consumers, you must register for non-Union OSS (typically in Ireland or the Netherlands), charge each customer their local VAT rate, and file quarterly returns. B2B sales to VAT-registered EU businesses still use reverse charge at 0%.

What is the easiest way to handle EU VAT as a solo founder?

Use a Merchant of Record like Paddle, Lemon Squeezy, or Polar. They become the legal seller, charge the correct VAT, handle OSS filing, and absorb audit risk for a flat 5-7% of revenue. For pre-PMF founders this is almost always cheaper than building compliance yourself. Switch to Stripe Tax once you cross roughly $50k MRR.

What happens if I just ignore EU VAT?

Probably nothing until you get noticed, then a lot. Penalties range from 5% to 30% of unpaid VAT plus interest, and DAC7 platform reporting means tax authorities increasingly see your sales through payment processors and app stores. The "fly under the radar" approach worked five years ago; in 2026 it ends in a back-VAT bill that often exceeds your annual revenue.

Do I need to register for VAT in every EU country?

No. The One Stop Shop (OSS) scheme lets you register in one EU member state and file a single quarterly return that covers all 27 countries. Union OSS is for EU-established sellers; Non-Union OSS is for non-EU sellers. You pick one member state of identification, and that is your only registration point.

Is Stripe Tax enough on its own?

Almost. Stripe Tax calculates the correct VAT, validates EU VAT numbers via VIES, applies reverse charge for B2B, and exports OSS-ready reports. It does not file the return for you. You either file it yourself through the OSS portal (15-30 minutes per quarter) or pay an accountant €100-300 per quarter to file it. For most founders, Stripe Tax + accountant filing is the cheapest defensible setup once you have real EU revenue.