An agency puts out a tender for 200,000 words of legal translation. You send your proposal - 8 years of experience, portfolio, references. The reply: “Thank you, but we only consider ISO 17100-certified providers.” That’s 5,000-10,000 euros for certification vs. a contract that would pay for itself in a month. The question isn’t what ISO 17100 is - it’s whether you actually need it.
What ISO 17100 is and what it requires¶
ISO 17100:2015 is the international standard for translation service requirements. It replaced the European EN 15038 (2006) and became the first global standard for the translation industry.
Here’s the key thing: ISO 17100 is a process standard, not a quality standard. It doesn’t say “the translation must be good.” It says “your workflow must follow certain rules so the probability of a good result is as high as possible.”
Translator qualifications¶
The standard spells out who can translate. A translator must meet at least one of three criteria:
- A degree in translation, linguistics, or language studies
- A degree in any other field plus at least 2 years of full-time professional translation experience
- At least 5 years of full-time professional translation experience (no degree required)
On top of that, the standard requires six competencies: translation, linguistic, research, cultural, technical (working with CAT tools), and domain-specific (subject matter expertise).
The four-eyes principle¶
This is probably the most well-known ISO 17100 requirement. Every translation must go through two people: the translator does the translation, and a different qualified linguist does the revision (bilingual editing). The same person can’t both translate and revise their own work.
For an agency, this makes sense - they usually have revisers on staff anyway. For a freelancer, it’s a problem because you need to find a colleague to check every job.
What else the standard requires¶
- A documented project handling process (from receiving the order to delivery)
- Data protection and confidentiality protocols
- Project archiving
- A client feedback handling process
- Terminology management
The standard explicitly excludes machine translation plus post-editing (MTPE) from its scope - there’s a separate standard for that, ISO 18587.
Freelancer vs. agency: who can get certified¶
For agencies¶
ISO 17100 was designed for agencies and translation companies. The process is straightforward: hire an accredited body (DIN CERTCO, DEKRA, TÜV SÜD in Germany, or Bureau Veritas, ATC Certification internationally), pass a two-stage audit (documentation review + on-site visit), get a certificate valid for 3 years with annual surveillance audits.
Cost: 5,000-10,000 euros for initial certification, depending on company size, number of language pairs, and process complexity. Recertification runs about 2,000 euros every two years.
For freelancers¶
This is where it gets tricky. ISO 17100 certification is formally designed for organizations, and for a solo freelancer it’s:
- Expensive (the same 5,000-10,000 euros - that’s serious money for an individual translator)
- Full of requirements that don’t make sense for one person (organizational procedures, company-level project management)
- Dependent on the four-eyes principle, which means you need a second linguist
Alternatives for freelancers:
ITI Qualified status (UK) - The Institute of Translation and Interpreting offers MITI/FITI status, which confirms compliance with the parts of the standard applicable to individuals. Cost: GBP 62 + VAT for existing members.
DIN CERTCO matrix certification (Germany) - Lets freelancers certify in association with other translators, splitting the costs.
Working to the standard without a certificate - If you meet the qualification requirements and regularly use a second linguist for revision, you’re de facto working in compliance with ISO 17100. You can state “working to ISO 17100 standards” on your CV without an official certificate.
BDU membership - For translators in Germany, BDU (Bundesverband der Dolmetscher und Übersetzer) membership or passing the state exam can serve as an alternative qualification credential.
ISO 17100 vs. ISO 9001 vs. ISO 18587: what’s the difference¶
| Aspect | ISO 17100 | ISO 9001 | ISO 18587 |
|---|---|---|---|
| Covers | Translation services | Any industry (general quality) | MT post-editing |
| Focus | Translation process, linguist qualifications | Organizational quality management system | Process and qualifications for MTPE |
| Four-eyes principle | Mandatory | Not specified | Mandatory |
| Translator requirements | Specific (degree or experience) | None | Same 6 competencies |
| Best for | Translation agencies and bureaus | Any organization | Companies with MTPE workflows |
Many agencies hold both ISO 17100 and ISO 9001 at the same time - the first covers translation specifics, the second covers organizational processes. If you’re planning to certify, auditors can combine ISO 9001, 17100, and 18587 checks into a single audit, saving you time and money.
Is ISO 17100 worth it in 2026: real numbers¶
Here’s where it gets interesting. According to the ELIA (European Language Industry Association) 2025 survey:
- ISO 17100 and ISO 9001 certification levels among language companies are gradually declining
- About 30% of language companies have no certification at all
- Only 22% of clients require any certification from their providers
- ISO 17100 demand from clients dropped from 23% to 18%
But here’s the paradox: over half of language service companies still hold ISO 17100, even as client demand drops.
Criticism of the standard¶
There are things worth knowing before you invest:
ISO 17100 doesn’t cover modern workflows. The standard is “built around human translation” and doesn’t include AI tools, MTPE, or the hybrid processes most translators use today. GALA (the largest industry association) has publicly criticized this limitation.
It’s a process standard, not an output standard. ISO 17100 doesn’t define translation quality metrics. Following the process doesn’t guarantee good output - it just increases the probability.
Qualification requirements don’t match market reality. The standard requires a university degree or 5 years of experience, which doesn’t reflect how many people enter the profession today.
There’s already ISO 5060 - a newer standard for evaluating translation output that focuses on results rather than process. Worth keeping on your radar.
When ISO 17100 still makes sense¶
- You’re an agency bidding on contracts with large corporations or government institutions - it’s often a mandatory requirement there
- You work with pharma or legal sectors where process standardization is critical
- You need a competitive edge in an oversaturated market
- You want to formalize your processes - even without certification, implementing ISO 17100 as an internal standard improves how you work
When ISO 17100 isn’t worth the money¶
- You’re a freelancer with 3-5 regular clients who know and trust you
- You work primarily with MTPE - ISO 17100 doesn’t cover that, you need ISO 18587
- Your clients are small and medium businesses that never ask about certification (those same 78% of clients who don’t care)
- You’re just starting out and 5,000-10,000 euros is a significant chunk of your annual income
What’s next: the standard update¶
In July 2025, ISO registered the ISO/AWI 17100 (Edition 2) project - an update to the standard. It’s at an early stage of development, and publication isn’t expected before 2027-2028.
What’s planned: the standard should finally address “the much increased use of MTPE and other non-human methods of translation in modern translation workflows.” There’s an ongoing debate about changing the terminology from “machine translation” to “non-human translation” and strengthening qualification requirements for post-editors.
If you’re on the fence about certification right now - it might be worth waiting for the new version, which should be more relevant to how translation actually works today.
FAQ¶
How much does ISO 17100 certification cost?¶
For an agency - 5,000 to 10,000 euros for initial certification, depending on company size and number of language pairs. Recertification audits run about 2,000 euros every two years. For a freelancer, full certification costs the same (the standard doesn’t differentiate by size), which is why most solo translators go for alternatives - ITI Qualified status (GBP 62 + VAT) or matrix certification through DIN CERTCO.
Is ISO 17100 mandatory for working as a translator?¶
No. ISO 17100 is a voluntary standard. No country requires it for legal translation work. But certain corporate clients or government institutions may include it as a tender requirement. According to ELIA data, only 22% of clients ask about certification.
How long does the certification process take?¶
3 to 6 months for a small agency. The process includes: gap analysis between your current processes and the standard’s requirements, implementing changes, selecting an accredited body, and a two-stage audit (documentation review + on-site visit). The certificate is valid for 3 years with annual surveillance audits.
Can a freelancer claim ISO 17100 without official certification?¶
You can’t write “ISO 17100 certified” without a certificate - that would be misleading. But if you meet the standard’s qualification requirements and follow its processes (including revision by a different linguist), you can state “working to ISO 17100 standards” or “processes aligned with ISO 17100.” That’s honest and doesn’t break any rules.
What’s the difference between ISO 17100 and ISO 18587?¶
ISO 17100 covers human translation with revision - the classic “translator then revisor” chain. ISO 18587 covers post-editing of machine translation - the “machine then post-editor” chain. If you’re doing MTPE work, ISO 18587 is the one you need. Many agencies certify under both standards to cover both workflows.