UK flights recover after NATS outage: what passengers can claim

NATS says its operations are stable after a flight-processing failure on September 8, but passengers should still confirm an individual flight with the operating airline. More than 2,000 UK arrivals and departures were cancelled across September 8 and 9 as airlines worked to return displaced aircraft and crews to their schedules.

The UK Civil Aviation Authority now says disruption directly caused by the outage, including its knock-on effects, is likely to count as extraordinary circumstances. That makes fixed compensation unlikely in those cases. It does not remove an airline's duty to provide care or the passenger's cancellation choice between a refund and rerouting when UK261 applies.

The traveler decision: Check the flight in the operating airline's app or website before leaving, even if an airport board says flights are operating. If the flight is cancelled, choose between a refund and rerouting deliberately. Keep itemised receipts for reasonable meals, hotel and hotel transport because care rights are separate from any claim for cash compensation.

NATS restored the system, not every flight

NATS' incident log says the problem began in its flight-processing system on September 8. At 15:25, flights were still departing and UK airspace remained open, but the flow was restricted while engineers worked.

NATS said at 19:30 that the fault was resolved and the system was operating normally. Its final 22:10 update warned that the recovery was complex and would take time across the aviation network.

At 12:55 on September 9, NATS said its operations were stable and that it was supporting airline and airport recovery. NATS also said it would investigate what happened and identify any further action. The CAA says NATS will provide a technical report shortly, while the government has asked the regulator to conduct a separate independent review.

That distinction explains the second day of disruption. A flight needs more than an available airspace slot. It also needs the aircraft, legal crew hours, airport stand, ground handling and passengers in the right place. Restoring the central system cannot instantly rebuild all of those sequences.

More than 2,000 flights were cancelled across two days

The BBC's incident report said the number of flights cancelled or unable to depart across September 8 and 9 had risen above 2,000 by Wednesday evening, based on Cirium data. This is an incident total, not the status of a flight booked for September 10.

The same report said Heathrow, Gatwick, Manchester and Birmingham were the most affected airports. Heathrow and Gatwick described their operations as recovering on September 9, while airlines continued to reposition crews and aircraft. A system-wide recovery does not mean every route has recovered at the same time.

These airport summaries are not permission to travel without checking. One terminal can be busy while another airline operates normally. Use the Heathrow departures board, Gatwick flight board and the operating airline's booking record. A codeshare flight should be checked under the carrier that actually operates it.

Do not travel on an unconfirmed booking

An airport may be open while a specific flight is cancelled. Check the booking before beginning an expensive airport transfer, then check again before bag drop closes.

Save these details offline:

• the airline booking reference and ticket number;
• the operating carrier and flight number;
• the original schedule and any cancellation message;
• the replacement booking and seat status;
• baggage receipts and bag-tag numbers; and
• the airline's disruption and expense-claim links.

If the app and airport board disagree, contact the airline. Airport staff do not control another company's rerouting inventory. Screenshots with visible times can also help explain later claims.

A cancelled flight gives a refund or rerouting choice

The UK Civil Aviation Authority's cancellation guidance says a covered passenger can choose a refund for unused ticket portions or an alternative journey.

Someone who still needs to travel should not accept a refund casually. Taking the money can end the airline's obligation to reroute that journey. Ask for the earliest reasonable alternative, including another carrier or suitable transport when it would arrive significantly sooner, and keep the airline's answer.

A traveler who abandons a connecting itinerary after part of it has been flown may also be entitled to return to the original departure point. Separate tickets are different: a later airline does not automatically inherit responsibility for a self-transfer missed because the first booking failed.

Care continues even when the cause is outside the airline

Care and cash compensation are different rights. For a covered cancellation, the CAA says the airline must provide reasonable food and drink, communication, and a hotel plus transport when rerouting requires an overnight wait. The cause of the disruption does not remove that care duty.

For delays, care starts after two hours on flights under 1,500km, three hours on flights from 1,500km to 3,500km, and four hours on longer flights. The CAA's current delay guidance sets out the full test.

Ask the airline to arrange care first. If it cannot help, book something reasonable, retain itemised receipts and follow its expense process. Luxury rooms, alcohol and avoidable extras are unlikely to be reimbursed.

The CAA says fixed compensation is unlikely for directly caused disruption

UK261 fixed compensation is not automatic just because a flight arrived several hours late. Timing, route coverage and the cause all matter. An airline can reject fixed compensation when extraordinary circumstances outside its control caused the disruption and it took reasonable measures.

In its September 9 statement about this NATS outage, the CAA says the initial disruption and directly caused knock-on effects are likely to be extraordinary circumstances. It therefore considers passengers unlikely to receive fixed compensation for cancellations or delays caused in those circumstances.

The regulator also says this interpretation is guidance, not a ruling on every individual case. Ask the airline for the precise reason affecting the specific flight. A later cancellation can involve several causes, including a separate airline problem. If the airline relies on extraordinary circumstances, it should explain why. A rejected claim can move to the airline's Alternative Dispute Resolution provider, if it belongs to one, or the CAA's Passenger Advice and Complaints Team after the required complaint process.

A delay beyond five hours creates another decision

If a covered delay reaches five hours, the CAA says the passenger can decide not to travel and request a refund for unused flights. On a through booking that has already begun, the airline must also arrange a return to the original departure point when the passenger abandons the journey.

This is not the same as waiting for a later flight. A traveler who still wants the trip should continue with rerouting and care rather than select the refund option by mistake. Capture the choice and airline confirmation in writing.

Missed connections depend on one booking or two

A protected through booking is assessed to the final ticketed destination. The operating airline should reroute a passenger who misses the connection because the first flight was disrupted, and the care test applies to the resulting wait.

With separate tickets, each flight is treated on its own. The first airline generally does not have a statutory duty to deliver the passenger to the last destination on an unrelated booking. Contact the second airline before departure closes, then check travel insurance and any protection offered by the booking platform.

Do not buy an expensive replacement journey until the responsible airline has had a reasonable chance to reroute, unless waiting is genuinely impractical. Record every attempt to contact it.

Protect updates, battery and data during the backlog

Airport Wi-Fi can be congested during a mass disruption. Keep the airline app signed in, download the itinerary, store the booking reference in a note and carry a charged power bank that meets the airline's cabin rules.

A United Kingdom Roaming eSIM can provide independent data for a UK-only stay. Travelers connecting through Dublin or Belfast can compare Ireland and UK, while a wider reroute may fit a Europe or Global 120 Areas plan after every destination is checked.

The selected card controls allowance, validity, activation, hotspot support, networks and reloadability. Mobile data can deliver an airline update or help book a train. It cannot restore a flight, guarantee a notification or change passenger rights.

Ten questions about the UK NATS flight disruption

Is the NATS system still down?

No. NATS said its system was operating normally at 19:30 BST on September 8 and described its operations as stable at 12:55 on September 9. An individual airline may still change a flight during recovery.

Should I travel to the airport?

Only after the operating airline confirms the flight. Check again before leaving because an airport can be open while one airline cancels a service.

What can I choose if my flight is cancelled?

For a flight covered by UK law, choose a refund for unused ticket portions or rerouting at the earliest opportunity or a later suitable date.

Must the airline provide a hotel and meals?

It must provide reasonable care when UK261 applies and the wait meets the relevant conditions. This can include meals, communication, overnight accommodation and transport to it.

Can I book my own hotel when the airline does not help?

The CAA says reasonable self-arranged care can be claimed when the airline cannot organise it. Ask first, avoid luxury spending and keep itemised receipts.

Does the NATS failure guarantee cash compensation?

No. The CAA says directly caused disruption and knock-on effects are likely to be extraordinary circumstances, so fixed compensation is unlikely in those cases. The regulator says each case remains fact-specific. Care, rerouting and refund rights are separate.

What happens after a five-hour delay?

A covered passenger can abandon the trip and request a refund for unused flights. Someone who still wants to travel should not choose that option inadvertently.

What if I miss a connecting flight?

On one through booking, the airline should reroute to the final destination. On separate tickets, protection generally applies to each individual flight rather than the full self-transfer.

Can I claim a replacement train or another airline?

Ask the responsible airline to reroute first. The CAA says a significantly earlier alternative carrier or suitable transport may be appropriate, but document the request before buying independently.

What evidence should I keep?

Keep the original and replacement itinerary, cancellation reason, screenshots, boarding documents, contact attempts and itemised receipts for reasonable care expenses.

Evidence for the September 8 NATS outage

NATS' incident log establishes the fault, open-airspace boundary, restoration and stable-operations update. The CAA's September 9 statement establishes its incident-specific view of compensation, care and rerouting. The BBC's September 9 report supplies the two-day cancellation total attributed to Cirium and the six-month independent-review timetable.

We will update this page for a material NATS finding, recovery change, CAA ruling or corrected cancellation total. Airport and airline boards remain the source of truth for an individual flight. Later changes to this incident belong on this URL rather than a second September NATS page.