KLM online check-in: how it works

With KLM, online check-in opens 30 hours before departure, and 24 hours before on flights to and from the United States. You can go through it on the KLM website or in the airline's app, and the boarding pass comes to you automatically once you're done. Travelling with hand baggage only, you can in most cases head straight for security when you reach the airport.

Below we set out when each way of checking in opens, what you need before you start, how the process runs and what's left to do once you're at the airport.

Online check-in opens 30 hours before the scheduled departure time. On flights to and from the United States it opens 24 hours before instead.

The kiosks at the airport work to that same 30-hour window, so if online check-in hasn't gone through, or you'd rather not deal with it on your phone, the kiosk will still issue your boarding pass. KLM points out that not every airport has them, and where they exist they sit near the check-in desks.

The deadline that bites on the day is the one at the airport, and it applies however you checked in. On European flights the desks and the baggage drop-off both close 40 minutes before departure; on intercontinental flights, 60 minutes before. The exact closing time for your own flight is printed on your boarding pass.

At the other end of the window, the desks open 2 hours before a European flight and 3 hours before an intercontinental one. KLM's advice is to be at the airport by then, since there can be a queue at the desks and at the self-service drop-off points alike.

Before you start, have the following to hand:

• your booking code, the six-character reference such as ACQ167, or your ticket number, which runs to 13 or 14 digits;

• the passenger's last name, as it appears on the booking;

• the flight number, which on a KLM flight begins with KL;

• your passport or identity card, depending on where you're flying.

The form asks for the first three together rather than any one of them, so it's worth having the booking confirmation open in front of you.

The other way in is the account. Signing in to Flying Blue, the Air France-KLM loyalty programme, is the first option the check-in page offers, and it means not typing the booking details at all.

The process takes a few minutes and runs the same way on the website and in the app.

How to check in online with KLM:

1. Go to the KLM website or open the KLM app.

2. Sign in to Flying Blue, or enter the booking code or ticket number with the last name and the flight number.

3. Work through the steps and confirm the details you're asked for, travel documents included.

4. Finish the check-in, and the boarding pass comes through digitally.

The KLM website and the KLM app take you through the same check-in, and the difference is in where the boarding pass ends up. Both are set out below.

If you booked through an agent or a site like Expedia

Buying through an agent doesn't change where you check in: it's still KLM, unless another airline is operating the flight. The details asked for are the same, too, the booking code or ticket number with the last name and the flight number.

The catch is the code. An agent or an online travel agency gives you a reference of its own, and that isn't always the six-character code KLM uses to find the booking in its own system. If the one you have doesn't work, there are two ways round it:

• look again at the confirmation email from the agency, where the airline's own reference is often shown separately, under wording such as "airline booking reference";

• use the ticket number instead, the 13 or 14-digit sequence, which the check-in form takes in the same field as the booking code.

If neither turns anything up, the agency can give you the KLM booking code.

Once check-in is done the boarding pass comes through on its own, and you pick where it lands:

• in the KLM app;

• in My Trip on the website, ready to download whenever you want it;

• by email;

• as a private message on WhatsApp or Messenger.

None of those needs printing: KLM's position is that any of the digital versions is valid. If you'd rather have paper, you can print it at home after checking in, or pick one up at the airport from a self-service kiosk or a check-in desk. From the email or from the app, the pass can also go into your phone's wallet.

If KLM has still to check your travel documents, such as a passport or a visa, what arrives after check-in may be a check-in confirmation rather than a boarding pass. The boarding pass is then handed over at the airport, and KLM's instruction is to collect it at the check-in desk.

At the airport

What's left when you get there depends on your baggage.

• With hand baggage only, in most cases you can go straight through to security.

• With checked baggage, it goes to a KLM desk or, where the airport has them, to a self-service drop-off point.

Both close 40 minutes before a European flight and 60 minutes before an intercontinental one, and the closing time for your own flight is on the boarding pass.

Online check-in covers most bookings, but not all of them. KLM lists these as cases where the check-in is done at the airport desk instead:

• passengers who have requested assistance;

• anyone travelling with a pet, whether it's in the cabin or in the hold;

• unaccompanied minors.

A flight operated by a partner airline is a different case: the check-in follows that airline's rules rather than KLM's.

You checked in in good time, you got to the gate when you were meant to, and your booking was confirmed. Even so, a delay, a cancellation or an overbooked flight can still get in the way of your plans.

If that happens and the airline is responsible, UK261 entitles you to compensation of up to £520 per passenger, depending on how far you were due to fly. The rules cover every flight departing from a UK airport, whichever airline you're travelling with.

If your KLM flight departs from an airport in the EU, the equivalent European rules apply instead, under Regulation EC 261/2004.

Being turned away at the gate is covered too: our guide to denied boarding sets out where you stand. And to see what you may be owed for your own flight, start with our KLM compensation page.

Keeping track of your KLM flight

With check-in out of the way, all that's left is the wait. It's well worth keeping an eye on your flight status in the meantime, particularly if you have a connection to make or someone meeting you at the other end.

KLM's Flight Status page takes a flight number or a route and gives arrival and departure times as they stand, for KLM flights and for partner airlines alike. Up to six flights can be saved there, and the tracker runs as far as 60 days ahead.

You could also use the free AirHelp app, which does one thing more: if your flight is delayed by more than 3 hours, is cancelled, or you're denied boarding, the app checks automatically whether you're entitled to compensation under UK261/EC 261 and lets you know.

With the AirHelp app you can:

• receive real-time notifications about delays, cancellations, gate changes and baggage reclaim;

• scan your boarding pass to add your flight quickly;

• share your flight status with whoever is picking you up;

• automatically check whether a disruption entitles you to compensation of up to £520;

• start your compensation claim straight from the app, with no paperwork.

The app is free and available on iOS and Android.