The verdict in three sentences
For a company getting 1,500 contracts a month signed on paper, integrating an e-signature API pays for itself within months: EUR 4,000 to 12,000 excl. VAT of development and EUR 0.50 to 2 per signature. The decisive choice is the eIDAS signature level (simple or advanced) for each contract type, not the vendor. Average contract turnaround drops from 6 days to 1 day.
Simple, advanced or qualified: which eIDAS level to choose
The EU eIDAS regulation defines three levels. All carry legal value, but the burden of proof differs if a signature is challenged. For routine service contracts, a simple signature with an audit trail is enough in the vast majority of cases. Advanced signatures are needed for high-value commitments.
| eIDAS level | Signer verification | Typical use case | Indicative price per signature 2026 |
|---|---|---|---|
| Simple | SMS or email code, audit trail | Service contracts, purchase orders, quotes | EUR 0.50 to 1.00 |
| Advanced | Verified ID document, personal certificate | High-value contracts, commercial leases | EUR 1.50 to 3.00 |
| Qualified | Face-to-face or certified video verification | Deeds with presumption of reliability, public tenders | EUR 3 to 8 |
| Electronic seal | Company certificate, no human signer | Invoices, mass-generated certificates | EUR 0.10 to 0.30 |
| Evidential archiving | Digital vault, 10-year retention | All contracts to retain | EUR 0.05 to 0.20 per document per year |
The operations director can therefore mix levels: simple signatures for 90% of contracts, advanced for the 10% above an amount threshold agreed with legal.
Integration cost and vendor comparison
Integration means generating the PDF from the application, sending it to the API, tracking statuses by webhook, then retrieving the signed document and audit trail. Complexity depends on the number of contract templates, multi-signer workflows and archiving.
| Integration scope | Content | Estimated budget (EUR excl. VAT) | Timeline |
|---|---|---|---|
| Basic | 1 to 2 templates, 1 signer, status webhook | 4,000 to 6,000 | 2 weeks |
| Standard | 5 to 10 templates, multiple signers, automatic reminders | 6,000 to 9,000 | 3 to 4 weeks |
| Advanced | Mixed levels, evidential archiving, dashboard | 9,000 to 12,000 | 5 to 6 weeks |
| Initials and dynamic fields option | Automatic field placement | 1,000 to 2,500 | 1 week |
| In-branch tablet signing option | Face-to-face mode | 1,500 to 3,000 | 1 week |
On the vendor side, Yousign (French) offers API plans from a few hundred euros a month with included volume, Universign (French) is valued for timestamping and seals, and Docusign is pricier but unavoidable if your clients are English-speaking. At 1,500 signatures a month, negotiate an annual package: unit price gaps can reach 40%.
What the integration actually changes
| Indicator | Before (paper, scan) | After (embedded API) |
|---|---|---|
| Average turnaround | 6 days | 1 day |
| Incomplete or wrongly signed contracts | 8 to 12% | Under 1% |
| Printing, mailing, scanning cost | EUR 3 to 5 per contract | EUR 0 |
| Admin time per contract | 12 minutes | 2 minutes |
| Finding an archived contract | 5 to 15 minutes | A few seconds |
Mini case study
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Nathalie, operations director of a maintenance services company in Nantes, handles 1,500 contracts a month. Current paper cost: EUR 4 in material costs plus 10 minutes of admin work saved at EUR 30 an hour, so EUR 9 per contract, or EUR 13,500 a month. Cost after integration: 1,350 simple signatures at EUR 0.80 and 150 advanced at EUR 2, so EUR 1,380 a month, plus a standard integration at EUR 8,000 excl. VAT. Net monthly savings reach about EUR 12,000: the integration pays back in under 3 weeks, not counting revenue collected 5 days earlier.
FAQ
Is a simple e-signature valid in court?
Yes, French civil code article 1367 and the eIDAS regulation give it legal value. If challenged, the audit trail (timestamp, IP address, SMS code) is produced; for contracts above EUR 50,000, an advanced signature strengthens your position.
Do we need to replace our business application?
No, the API plugs into the existing application if it already generates PDFs. Count EUR 4,000 to 6,000 excl. VAT for a basic integration in 2 weeks.
What if we switch e-signature vendors?
An abstraction layer in the code (about EUR 1,500 more) lets you move from Yousign to Universign or Docusign in a few days. Contracts already signed remain valid and archived.
How long should signed contracts be kept?
The commercial limitation period in France is 5 years, but many companies keep 10 years. Evidential archiving costs EUR 0.05 to 0.20 per document per year.
Does data leave Europe?
Yousign and Universign host in France; Docusign offers EU hosting on enterprise plans. Check this in the contract to stay GDPR compliant.
Let's scope your project. We scope your e-signature integration (contract templates, eIDAS levels, archiving) for an indicative budget of EUR 4,000 to 12,000 excl. VAT and go-live in 2 to 6 weeks. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
