London is home to thousands of firms that trade with Spain and Latin America. Sooner or later, a Spanish contract lands on a desk and someone has to decide who translates it. That decision can shape the whole deal.

Why contract wording matters

A contract is not just a text. It is a set of rights, duties and deadlines. When it moves between Spanish and English, one loose phrase can shift who pays, who delivers and who is liable.

Words such as "garantía", "fianza" or "resolución" have no perfect English twin. A good translator knows which English term fits the legal effect, not just the dictionary entry.

Different legal systems, different habits

Spain follows a civil law tradition, while England uses common law. Spanish contracts are often shorter and rely on the code to fill the gaps. English contracts spell out almost everything.

If you want a clearer picture of how these two systems think, our guide on civil law versus common law explains the main differences in plain terms.

A faithful translation keeps the legal intent, even when the sentence structure has to change.

When a plain translation is not enough

Some documents must be certified before a UK body accepts them. Court filings, company registration papers and powers of attorney are common examples. Check the requirements of the receiving office before you order anything.

For contracts, certification is not always compulsory, but many solicitors ask for it anyway. It shows that the translator stands behind the accuracy of the text.

Choosing the right specialist

Look for a translator who handles legal translation services every week, not someone who does it once a year. Ask about their experience with commercial agreements, shareholder papers and lease terms.

Request a short sample or a glossary of the key terms. This quickly shows whether they understand your sector.

Terminology you should lock down early

Before translation starts, agree on a list of defined terms. Company names, product names, job titles and legal entities should stay the same across every document. A shared glossary saves time and prevents clashes between drafts.

Pay special attention to the names of Spanish company forms. "Sociedad Limitada" and "Sociedad Anónima" are usually kept in the original with a short English explanation, rather than forced into a UK equivalent.

Numbers, dates and currencies

Spanish documents write dates as day, month, year and use a comma for decimals. English readers may misread 1.500,50 as a very different amount. Make sure the translator converts formats consistently and flags anything unclear.

The same goes for currency. Keep the original currency in the text and add conversions only where the contract allows it.

Review and sign off

Ask a bilingual lawyer or a trusted colleague to read the final version against the original. A second pair of eyes catches omissions that automatic checks miss.

Keep a signed copy of both language versions. State in the contract which version prevails if a dispute arises. This single clause prevents many arguments later.

Confidentiality and data handling

Contracts often contain pricing, ownership and personal data. Choose a provider who signs a confidentiality agreement and uses secure file transfer. Avoid sending sensitive files through public tools or unprotected email.

Timing a legal translation project

Do not leave translation to the last minute. A typical contract needs time for drafting, review and corrections. If a signing date is fixed, work backwards and allow a buffer for questions from both sides.

Urgent jobs are possible, but they leave less room for terminology checks. Plan ahead and the result will be better and cheaper.

Common mistakes to avoid

The most frequent errors are using machine output without review, mixing British and American spelling, and translating names that should stay unchanged. Each one can create confusion in a legal setting.

Another mistake is ignoring annexes. Schedules, price lists and technical specifications are part of the contract and must be translated with the same care as the main text.

Official guidance for UK businesses

For general rules on trading with other countries, see the Department for Business and Trade pages. They give a useful starting point for exporters and importers.

Questions to ask before you order

Ask who will translate, who will review, and how corrections are handled after delivery. Find out whether the provider keeps a translation memory so that repeated clauses stay consistent across all your agreements.

Also ask about turnaround for amendments. Contracts change, and a provider who can update a single clause quickly saves you from paying for a full retranslation each time.

Finally, confirm how the final files are delivered. A signed PDF plus an editable version makes life easier for your legal team.

Keeping a record for future disputes

Store the original, the translation and all email exchanges about wording in one shared folder. If a disagreement appears months later, you can show exactly what was agreed, when, and by whom.

This habit also helps new team members. They can read earlier contracts and see how key terms were handled, which keeps your documents consistent as the business grows.

Final thoughts

A Spanish contract in London does not have to be risky. With a clear glossary, a qualified legal translator and a final review, you protect your business and keep the relationship with your partner smooth.