An employment contract extension letter is a short, clear document that puts in writing an agreement to keep someone on the same terms for a defined period beyond the original end date. It is not a new contract in most cases; it is a confirmation that both sides want the existing arrangement to continue, with the same duties, pay and conditions unless something is expressly changed. Getting it right protects the employee's certainty and the employer's records, and it avoids the awkward gap where someone keeps working but nobody can point to a document explaining why.
These letters come up in many everyday situations. A fixed-term researcher needs a few more months to finish a project. A maternity cover arrangement is extended because the permanent post-holder has changed plans. A probationary period is stretched while training is completed. A seasonal worker is asked back for another busy period. A contractor on a rolling engagement is kept on while a permanent hire is recruited. Each situation calls for slightly different wording, and the tone should match the relationship: warm and appreciative for a long-serving employee, crisp and formal for a regulated or unionised workplace.
Below you will find six complete sample letters covering those scenarios, each with editable fields in square brackets so you can adapt names, dates and figures. Read the notes before each sample, because the details that matter most are the end date, whether any terms change, and what happens if the extension is not renewed. A letter cannot settle every legal question, and rules on fixed-term work, notice and continuity differ between countries and sometimes between regions. When the stakes are high, have a qualified employment adviser review the wording before you send it.
What an Extension Letter Should Contain
A useful extension letter answers four questions in plain language: who is being extended, what is being extended, until when, and on what terms. Start by identifying the original contract by its date or reference so there is no doubt which document is being varied. Then state the new end date clearly, using a full date rather than a vague phrase like 'the end of the quarter'. Confirm that all other terms remain unchanged, or list any specific changes such as a new rate of pay, different hours or a revised job title.
Include a short line about what happens at the end of the extension. If the role is genuinely temporary, say that the extension does not create an expectation of further renewal. If renewal is possible, say so honestly rather than leaving it ambiguous. Add practical details: whether the employee should sign and return a copy, who to contact with questions, and the date the letter takes effect. Keep the tone human. A sentence acknowledging the person's contribution costs nothing and makes the document easier to receive.
Finally, think about records. Keep a signed copy on the personnel file, update payroll and any HR system with the new end date, and diarise a review point before the extension expires. If the employee is on a visa, a training programme or a union-recognised grade, check whether the extension triggers any additional steps. The letter itself is simple; the surrounding administration is where mistakes usually happen.
Sample 1: Extending a Fixed-Term Project Role
This letter suits a project worker whose original contract ends soon but whose work is not quite finished. It is friendly, specific about the new end date, and careful to avoid promising permanent employment.
[Date]
[Employee Name]
[Employee Address]
Dear [Employee Name],
Re: Extension of your fixed-term contract of employment dated [original contract date]
I am writing to confirm that we would like to extend your fixed-term contract, which was due to end on [original end date], so that you can help us complete [project name] through to its final delivery.
Your contract will now end on [new end date]. All other terms and conditions of your contract remain unchanged, including your salary of [amount] per [period], your hours of [hours] per week, and your place of work at [location]. Your continuous service with the company is unaffected by this extension.
As before, this extension is for a fixed period linked to the project. It does not create any expectation of permanent employment or of further renewal beyond [new end date]. We will review progress in [month] and will write to you before the end date about next steps.
Please sign and return the enclosed copy of this letter by [return date] to confirm your agreement. If you have any questions, please speak to [contact name] on [contact details].
Thank you for your continued work on [project name]. We are glad to have you with us for this final phase.
Yours sincerely,
[Name]
[Job Title]
[Company Name]
I agree to the extension of my contract on the terms set out above.
Signed: ______________________ Date: ______________
[Employee Name]
Sample 2: Extending Maternity Cover
When a permanent employee's return date shifts, the person covering the role needs written confirmation quickly. This version is warm and reassuring, and it explains why the extension is happening without disclosing unnecessary personal details.
[Date]
[Employee Name]
[Employee Address]
Dear [Employee Name],
Re: Extension of your contract of employment dated [original contract date]
I am writing to let you know that the colleague you are covering for has extended their leave, and we would very much like you to continue in your current role during that period.
Your contract, which was due to end on [original end date], will now end on [new end date]. Your job title, duties, pay of [amount] per [period], hours and benefits remain exactly as they are now. The only change is the end date.
We have valued the continuity you have brought to [team or department] during this period, and we are grateful that you are able to stay on. As this remains cover for a temporary absence, the extension does not carry any promise of a permanent position, but we will keep you informed if the position becomes available.
Please confirm your agreement by signing and returning the enclosed copy by [return date]. If anything about the arrangement is unclear, [contact name] is happy to talk it through with you on [contact details].
With thanks,
[Name]
[Job Title]
[Company Name]
I agree to the extension of my contract on the terms set out above.
Signed: ______________________ Date: ______________
[Employee Name]
Sample 3: Extending a Probationary Period
Sometimes the issue is not the contract's end date but the probation period. This letter is direct and supportive, sets a clear review date, and explains what needs to improve or be completed before confirmation.
[Date]
[Employee Name]
[Employee Address]
Dear [Employee Name],
Re: Extension of your probationary period
Following our meeting on [meeting date], I am writing to confirm that your probationary period, which was due to end on [original probation end date], will be extended to [new probation end date].
This extension gives us time to complete [specific training, project handover or review] and to see your progress in [specific area]. Your pay, hours and other terms of employment are unchanged during this period. Your start date remains [start date], and your continuous service is not affected.
We will meet on [review meeting date] to review how things are going. Before then, [manager name] will arrange [support, training or check-ins] to help you settle into the role. If you have questions about what is expected, please raise them with [manager name] or [HR contact] at any time.
At the end of the extended period we will confirm your position in writing. If you would like to discuss this letter, please contact [contact name] on [contact details].
Yours sincerely,
[Name]
[Job Title]
[Company Name]
I acknowledge receipt of this letter and agree to the extension of my probationary period.
Signed: ______________________ Date: ______________
[Employee Name]
Sample 4: Extending a Seasonal or Rolling Engagement
Seasonal and rolling engagements need especially clear language about what happens when the busy period ends. This letter confirms the new dates and avoids implying that the arrangement will continue indefinitely.
[Date]
[Employee Name]
[Employee Address]
Dear [Employee Name],
Re: Extension of your seasonal contract dated [original contract date]
Thank you for your work during [season or period]. Demand has remained stronger than expected, and we would like to extend your engagement to help us through [specific period or event].
Your contract will now run until [new end date]. Your rate of pay of [amount] per hour, your shift pattern and your duties remain the same. Any accrued holiday and continuity of service will be treated in line with your original contract.
Please note that this extension covers only the period up to [new end date]. It does not guarantee work beyond that date, and any further engagement would be offered separately in writing. We will confirm the position before [new end date] so that you can plan accordingly.
Please sign and return the enclosed copy by [return date] to confirm your agreement. If you have any questions about shifts or pay, please contact [contact name] on [contact details].
We appreciate your flexibility and hope you will enjoy the rest of the season with us.
Yours sincerely,
[Name]
[Job Title]
[Company Name]
I agree to the extension of my contract on the terms set out above.
Signed: ______________________ Date: ______________
[Employee Name]
Sample 5: Extending a Contractor or Agency Engagement
Where the worker is engaged through an agency or as a contractor, the letter should be precise about the parties and avoid accidentally creating an employment relationship. This version is formal and refers to the governing agreement.
[Date]
[Contractor or Agency Name]
[Address]
Dear [Name],
Re: Extension of engagement under agreement dated [original agreement date]
We are writing to confirm that we wish to extend the engagement of [worker name] in the role of [role title], which was due to end on [original end date].
The engagement will now continue until [new end date]. The scope of work, the agreed rate of [amount] per [period], and the reporting arrangements set out in the original agreement remain unchanged. No other terms of the agreement are varied by this letter.
This extension is for the period stated above only. It does not create any obligation to offer further work, and any further extension will be confirmed separately in writing. Please ensure that [worker name] is available for the scheduled handover on [date] and that all timesheets are submitted as usual.
Please confirm acceptance of this extension by signing and returning a copy of this letter by [return date]. If you need to discuss any aspect of the arrangement, please contact [contact name] on [contact details].
Yours sincerely,
[Name]
[Job Title]
[Company Name]
Accepted for and on behalf of [Contractor or Agency Name]:
Signed: ______________________ Date: ______________
Name: ______________________ Position: ______________
Sample 6: Extending With a Change to Hours or Pay
An extension is a good moment to adjust terms if both sides agree. This letter is transparent about the change, confirms everything else stays the same, and gives the employee a chance to ask questions before signing.
[Date]
[Employee Name]
[Employee Address]
Dear [Employee Name],
Re: Extension of your contract of employment dated [original contract date]
I am pleased to confirm that we would like to extend your contract, which was due to end on [original end date], until [new end date].
In addition to the new end date, we propose one change to your terms: from [effective date], your [hours will increase to [number] per week / salary will increase to [amount] per [period]]. This reflects [reason, such as additional responsibilities or a revised role]. All other terms of your contract, including your job title of [job title], your place of work and your holiday entitlement, remain unchanged.
If you agree to these terms, please sign and return the enclosed copy by [return date]. If you would like to discuss the change before deciding, please contact [contact name] on [contact details] and we will arrange a time to talk it through.
Thank you for your contribution to [team or project]. We are glad to be extending your time with us.
Yours sincerely,
[Name]
[Job Title]
[Company Name]
I agree to the extension of my contract and to the change of terms set out above.
Signed: ______________________ Date: ______________
[Employee Name]
Send the letter before the original end date, not after it. A gap of even a few days can create confusion about continuity of service, pay and holiday accrual, and it is much harder to correct afterwards. If the decision is made at short notice, a short email confirming the key points can bridge the gap, with the formal letter to follow.
Match the wording to the reality. If further renewal is likely, do not write that it is impossible; if the role really is temporary, do not imply permanence. Honest language protects both sides and reduces the risk of disputes later. Keep a signed copy, update payroll and HR records, and set a reminder to review the position well before the new end date.
For anything beyond a straightforward date change, especially where terms are being altered, a probation is being extended, or the worker's immigration or union status is involved, take advice from a qualified employment adviser in your jurisdiction. They can check the letter against local rules and your own policies, and that review is worth the time.