Apology to a colleague regarding project mistake

The task

You made a significant mistake on a recent project at work.

Write a letter to a colleague who is affected by the mistake. In your letter:

→admit the mistake you made
→explain how the mistake happened
→outline the steps you are taking to fix it

Write at least 150 words. You do not need to write any addresses. Begin your letter: Dear Mr/Ms [Name],

Model answer

Band 8 sample letter

Band 8188 words. Names and details are invented; write your own.

Dear Ms Henderson,

I am writing to sincerely apologise for the significant error I made regarding the quarterly sales data provided for our joint presentation yesterday. I realise this oversight has caused you considerable stress and likely reflected poorly on your preparation.

The mistake occurred due to a technical glitch during the automated data migration process. I mistakenly pulled the draft figures from the internal server instead of the verified final report. Because I was rushing to meet the tight deadline, I failed to cross-reference the file names before sending them to you, which allowed the outdated information to slip through.

To rectify this immediately, I have submitted the correct, audited dataset to the department head this morning with a formal clarification memo attached. Furthermore, I am working with the IT team to implement a mandatory double-check protocol for all shared documents to ensure this never recurs. I would also like to offer my assistance in reformatting the slides to reflect the accurate figures, should you require it.

I deeply regret the inconvenience this has caused you and hope you can accept my apology.

Best wishes,

Julian Thorne

Write your own and get a band

Answer this prompt in a timed General Training writing test and get a band for task achievement, coherence, vocabulary and grammar, with the sentences to fix.

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Examiner's view

Why this scores well

A Band 8 response fully addresses all three bullet points with clear, logical development and a consistently appropriate semi-formal tone. A common Band 6 mistake is failing to provide a credible explanation for the error, instead offering vague or overly defensive excuses that lack professional maturity.

→Write to someone you know but not closely, such as a manager, landlord or neighbour, using their title and surname.
→Polite and friendly at once: a few contractions are fine, slang is not. Close with Yours sincerely or Kind regards.
→State the purpose in the first two sentences; small talk costs words you need for the bullets.

6 phrases

Useful phrases from the letter

oversight
an unintentional failure to notice or do something
data migration
the process of moving data between computer systems
cross-reference
to check the accuracy by comparing with sources
rectify
to put something right or correct a mistake
audited
officially examined for accuracy and completeness
inconvenience
trouble or difficulty caused to someone else

Frequently asked questions

Is this letter formal or informal?+

Semi-formal. Write to someone you know but not closely, such as a manager, landlord or neighbour, using their title and surname.

How many words should an IELTS General Training letter be?+

At least 150 words, and 160 to 200 is the comfortable range. Spend about 20 minutes on it and leave 40 for Task 2, which carries twice the marks.

What does the examiner look for?+

Keep practising

More apology letters

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