Templates8 min readUpdated: April 30, 2026

Example of an email for a complaint about flight delays or cancellations

The best complaint email is short, formal and full of specific information. No threats, no excess emotions and no mixing of different demands.

Main guide for this topic: Air passenger rights

What the email must contain

The email should contain the flight details, a brief description of the disturbance, what you are looking for and a list of attached evidence. If you are claiming a fixed fee, state that you are making the claim due to a delay, cancellation, missed connection or denied boarding.

Be sure to include the flight number, date, route, booking reference, planned arrival time and actual arrival time if you know it. When connecting, specify the final destination from the entire reservation.

You don't have to quote the law in ten paragraphs. Accuracy is more important than length. An airline needs a clear basis to find a flight and respond to a specific request.

Next step

Find out if you are owed up to EUR 600 in compensation.

The quick check combines flight details, route distance and basic evidence to assess your right.

Basic message example

Dear Sir/Madam, I am submitting a claim for flight [flight number] on the route [from-to], scheduled for [date]. The flight was [delayed/cancelled/diverted], and I arrived at my final destination [how late] compared to the planned time.

Please check the basis for the fixed fee and provide a reasoned answer. I am attaching the reservation confirmation, boarding pass and available communication about the disruption. Please confirm the receipt of the complaint and the reference number.

This text is intentionally short. If necessary, add a sentence or two explaining the specifics of the case, such as a missed connection, alternate flight, or denied boarding.

If you are also looking for costs

If you paid for a meal, hotel, transfer or new ticket yourself because the airline did not provide care, list it separately. Don't confuse that request with a fixed fee in the same sentence.

You can write: In addition to the request for a fixed fee, I also request a refund of reasonable expenses incurred during the waiting period, in the amount of [amount], according to the invoices attached.

Attach invoices and briefly explain why the expenses were incurred. If it was an overnight stay, state whether the airline did not provide a hotel or did not give clear instructions.

Case file

What Let Kasni organizes first

  • exact flight, date, route and booking reference
  • scheduled and actual arrival time
  • airline's stated reason and the evidence behind it
  • receipts for meals, hotel, transfer or a new ticket

If the flight is cancelled

For the canceled flight, add when you were notified of the cancellation and what was offered to you. This is important because the notice period and an alternative flight can change the right to compensation.

Example of addendum: I was notified of the cancellation on [date and time]. I was offered an alternative flight [number/route], which took me to my final destination [how late].

If you requested a refund instead of rerouting, state that as well, but clearly separate the issue of the ticket from the issue of fixed compensation.

If the request has already been rejected

If you are responding to a bounce, don't send the same email from the beginning. Refer to the reference number and ask for a more specific explanation.

Example: Thank you for your reply. Please specify which specific extraordinary circumstances affected the flight [flight number], in what period of time and what measures were taken to reduce the delay.

Such an answer is more useful than an argument. You are looking for facts that can be checked later.

What to avoid

Avoid threats, insults, capital letters, overly long travel descriptions, and claims you can't prove. If the case later goes to manual review, orderly and professional communication helps.

Do not send original documents unless necessary. Send copies or scans. Save the sent message, attachments, auto reply and reference number.

If you are not sure whether the case is strong, first enter the basic data on letkasni.rs. It is better to check the basis than to send a claim that mixes refund, voucher, expenses and compensation without a clear structure.

Do not invent the exact arrival time if you do not know it. It is better to write according to the available data or attach a screenshot than to provide incorrect information that the airline can easily dispute later.

Also don't send different versions of the event in multiple messages. If you have to correct something, write clearly that you are supplementing the previous complaint and state what is being changed.

At the end of the email, you are looking for a reasoned response, not just a status. This is important if you need to check later if the rejection is specific or just a generic message.

Professional review

Why we do not stop at a generic rejection

Airlines often expect individual passengers to give up after the first short answer. A structured file, knowledge of the rules and procedural pressure change the speed and quality of the response.

Add a response deadline and contact information

At the end of the message, you can add a request that the airline provide a reasoned response within the relevant time frame and that all communications go to the same email. It helps to see later when silence is really a problem.

Provide the passenger's full name, contact email, phone number if desired and booking reference. If you are sending a request for several passengers, clearly state whether you are writing for all passengers from the reservation or just for yourself.

If you are sending attachments, please list them by name. For example: booking confirmation, boarding pass, cancellation message, hotel bill. This reduces the risk that the airline will later claim that the document was not sent.

Route, timing and airline responsibility

For example of an email for a complaint about flight delays or cancellations, first check whether the route is protected, then what actually happened, and only then which claim makes sense. Use Air passenger rights for the baseline rule and amounts, while this page checks the concrete scenario and the evidence that changes it.

The best approach is to build a short timeline. Write down the scheduled time, actual time, where you were when the problem happened, what the airline offered, what you accepted and what you paid yourself. That timeline later decides whether the case is about fixed compensation, ticket refund, expense reimbursement or only care rights.

If the case involves arrival delay, a missed connection, rerouting or an overnight wait, also check flight delay compensation. Most practical passenger questions eventually depend on how late the whole journey ended and whether the reason was within the airline's control.

Person typing an email on a laptop

Documents to save for review

The strongest evidence is evidence from the same day: boarding pass, booking confirmation, airline messages, app screenshot, departures-board photo, receipts for food, hotel or transfer and any written information received at the airport.

If the reason was explained verbally, write down the exact wording, time and place. If the reason changed, keep every version. The difference between a technical fault, air traffic control, bad weather, strike and crew shortage is not a formality; it is often the line between a strong and weak claim.

In the claim, do not only say that you want compensation. Include flight number, date, route, booking reference, scheduled and actual arrival time, a short timeline and a clear separation between fixed compensation and expenses you want reimbursed.

What if the airline rejects the claim

The airline's first reply is often not a full assessment. It may contain broad wording, an automatically selected category or an answer that covers only one part of the claim. Read it carefully: does it address the exact flight, date, final destination and concrete reason that caused the disruption?

If the answer does not mention evidence, timeline or the measures the airline took, send a short follow-up. You do not need to repeat the whole story. Ask for a precise explanation and attach the most important proof again. That follow-up often separates genuinely weak cases from cases that were only rejected superficially.