TL;DR

An offer letter is the formal document from an employer to a candidate confirming the terms of employment before the full contract is issued. It sets out the key conditions of the role and, when signed by the candidate, confirms their acceptance. It is not the employment contract, but it is the first binding signal of intent.

The Document Between Verbal and Contracted

A [verbal offer](/glossary/verbal-offer) accepted in a phone call is a start, but a signed offer letter is what moves the process from intent to commitment. Candidates use it to hand in notice. Hiring managers use it to close out other pipeline activity. Finance uses it to confirm headcount. The offer letter is the operational handshake that makes the hire real before the full contract arrives.

A well-constructed offer letter covers the essentials: job title and reporting line, start date, base salary and bonus structure, location and remote work terms, probationary period, notice period, and any conditions the offer is subject to (right to work verification, reference checks, background screening). It should be clear, not exhaustive. The employment contract carries the full legal detail. The offer letter establishes the headline terms.

Offer letters must be drafted carefully. In some jurisdictions, an offer letter that is too detailed can itself constitute an employment contract, creating obligations the employer may not have intended. In others, it may be used as evidence of the terms agreed if the subsequent contract diverges. Legal review of standard offer letter templates is not an optional exercise.

Conditional offers are the norm for roles requiring clearance, professional qualification verification, or background screening. The offer is made but does not become unconditional until specified checks are completed. The candidate is not formally hired until conditions are satisfied. This distinction matters when a check comes back with an issue.

Why It Matters for Recruitment

The offer letter is where deals fall apart if it's mishandled, and where deals close faster if it's handled well. Speed matters. A candidate sitting on a verbal offer for five working days while the offer letter goes through three rounds of internal approval is a candidate with time to take competitor calls. Offer letters should go out within 24 to 48 hours of verbal acceptance.

For recruiters, the offer letter stage requires active management. Confirming the candidate has received it, answering questions, handling negotiation on specific terms, and accelerating any internal delays -- all of this happens in the window between verbal offer and signed return. Candidates who go quiet during this phase are usually reconsidering. The recruiter's job is to know that before it becomes a withdrawal.

Compensation mismatches between what was discussed and what the letter states are a common source of late-stage candidate dropout. Numbers should match exactly. If there are discrepancies, they should be caught internally before the letter goes out, not by the candidate when they read it.

For contingent and fixed-term roles, an offer letter equivalent (sometimes called an assignment confirmation or engagement letter) performs the same function. The terms differ -- assignment duration, day rate, IR35 status -- but the need for written confirmation before the candidate serves notice or commits is identical.

In Practice

A technology company extends a verbal offer to a senior product manager at a total compensation of £95,000 base plus 15% bonus and three days per week remote working. The recruiter confirms acceptance over the phone on a Tuesday. The offer letter is issued Thursday morning, confirming all three elements exactly as discussed, subject to satisfactory reference checks and right to work verification. The candidate signs and returns it Friday afternoon and gives notice to their current employer the same day.

The hiring company's internal benchmark is a 48-hour turnaround from verbal acceptance to signed offer. In this case they hit it. The candidate doesn't receive a counter-offer because they're already committed on paper. The role starts in 90 days.

Key Facts