Is a verbal service contract with a Turkish contractor binding if there is no written agreement?

Yes. In Turkey, a verbal service contract can be legally binding even if nothing was signed, because for most contractor and service arrangements the law does not require a written form for the contract to exist. The real problem is usually not validity, but proving exactly what was agreed.

Why disputes are won or lost

If a dispute starts, the court will focus on the essentials: scope, price, timeline, deliverables, payment conditions, and whether both sides acted as if a deal already existed. That is where many verbal agreements become weak, because each side begins describing the deal differently once money or performance becomes disputed.

What can prove the agreement

A signed contract is not the only evidence. In practice, WhatsApp messages, emails, quotations, invoices, bank transfers, advance payments, revision requests, delivery records, voice notes, and the parties’ actual conduct may all help establish that a binding agreement was made and what its terms were. If the contractor started the work, requested payment, sent drafts, or accepted money, those facts usually carry real weight.

What a verbal deal usually does not protect well

This is the part many answers miss. Even if you can prove there was a deal, a verbal arrangement often leaves the most important protection clauses unclear or unusable: delay penalties, intellectual property ownership, confidentiality, termination rights, governing court, arbitration, change-order rules, and quality standards. Those are usually the terms that matter most once the relationship breaks down.

Do you need a lawyer

A lawyer is not legally required just to put the deal into writing. But if the project has commercial value, foreign elements, staged payments, technical deliverables, or IP risk, having the contract drafted properly is usually far cheaper than litigating later over an avoidable ambiguity.

Practical answer

So the short answer is this: yes, a verbal service contract may be enforceable in Turkey, but only as far as you can prove its terms. If the relationship is still continuing, the safest move is to formalize it now in a written agreement before the record becomes contested. If the dispute has already started, the priority is to secure the message trail, payment records, and performance evidence immediately.