Flight Claim Services That Handle Complex International Cases

Flight claim service international complex cases break the standard single-framework workflow. A New York to London round trip on a Delta-Virgin Atlantic codeshare, with a cancelled return and a missed onward connection in Paris, touches the 2024 US DOT refund rule, UK261, EU261, and the Montreal Convention simultaneously. Most platforms file one framework well and silently drop the others. The flight claim service international complex test is whether the platform runs parallel filings per jurisdiction and stacks Montreal Convention documented loss recovery on top of EU261 or UK261 fixed cash compensation when the documented losses exceed the cash entitlement.

Single-framework platforms leave money on the table on international trips. A complex case needs a platform that files per leg, per jurisdiction, in parallel.

• ›

  US DOT 2024 refund rule: covers US-departing flights and US-arriving flights on US carriers, plus all flights sold by US airlines. Cash refund for cancellation, 3+ hour domestic delay, or 6+ hour international delay.

• ›

  EU261: covers EU-departing flights (any operating carrier) and EU-carrier flights arriving in the EU. Fixed cash compensation EUR 250 to 600 plus refund and duty of care.

• ›

  UK261: covers UK-departing flights (any operating carrier). Same structure as EU261 with GBP amounts. See UK261 compensation US passengers complete guide.

• ›

  Montreal Convention: covers international carriage between Convention states (almost all commercial aviation). Documented loss recovery up to about USD 7,300 per passenger plus separate baggage liability up to about USD 1,800.

The frameworks are independent, not exclusive. EU261 cash compensation does not preclude Montreal Convention documented loss recovery. US DOT cash refund does not preclude EU261 cash compensation on the EU-departing leg of the same trip.

Codeshare flights are sold under one airline's code (the marketing carrier) but operated by another (the operating carrier). EU261 places the obligation on the operating carrier. US DOT places the obligation on the airline that sold the ticket. On a Delta-marketed flight operated by Virgin Atlantic from London to JFK, EU261 obligations sit with Virgin Atlantic but the DOT refund obligations sit with Delta. A flight claim service international complex platform should identify the right respondent per jurisdiction and file accordingly. Filing against the wrong carrier wastes weeks. See codeshare flight cancelled who is responsible airline and interline ticket cancellation: which airline pays compensation.

Take a JFK to Paris with onward to Rome, where the JFK to Paris leg is cancelled, you are rebooked the next day, and you miss the Paris-Rome connection. The recovery stacks: US DOT cash refund right on the JFK to Paris leg if you decline the rebook, EU261 cash compensation EUR 600 (long-haul) on the cancelled JFK to Paris leg if operated by an EU carrier or under EU rules, EU261 duty of care reimbursement (hotel, meals) for the overnight wait, EU261 cash compensation on the missed Paris to Rome connection if rebooking is delayed 3+ hours, Montreal Convention documented loss recovery for any prepaid Rome hotel or other downstream losses up to USD 7,300 per passenger.

Total recovery on a single complex trip can stack to USD 600 plus EUR 600 plus EUR 250 plus documented loss. A platform that only files one framework recovers a fraction of what the regulations entitle.

When an airline ceases operations mid-trip (Norwegian Air, Flybe, Wow Air, Thomas Cook, Aeromexico in past insolvencies), standard refund rules no longer apply because the airline has no assets to pay. Recovery shifts to ATOL protection (for UK package holiday bookings), supplier default coverage on travel insurance, credit card chargebacks, and Montreal Convention claims against successor entities. A flight claim service international complex platform should screen for insolvency risk at intake and route to the correct recovery channel immediately. See airline shut down getting refund credit card vs travel insurance vs ATOL.

• ›

  TravelStacks: handles US DOT at $19 flat, US denied boarding at 25%, EU261 and UK261 at 25 to 45% depending on escalation, and assists with Montreal Convention documented loss recovery. Single intake for multi-jurisdiction trips.

• ›

  AirHelp: strong EU261 and UK261 coverage with a global legal infrastructure. Limited US DOT depth. 35% commission across the board.

• ›

  Compensair: EU261 specialist. No US DOT or Montreal Convention practice. Best for pure intra-EU cases.

• ›

  Flightright: strong German legal team for contested EU261 claims, especially Lufthansa and Eurowings. Limited US.

• ›

  Specialist law firms (Bott & Co, Coleman Legal Partners): handle very large or complex cases on contingency, typically only worthwhile when the recovery exceeds USD 5,000.

For broader competitor comparison, see best flight compensation platforms compared 2026, compare flight disruption platforms for international trips, and airhelp alternatives after claimcompass shutdown.

• ›

  US DOT refund leg: $19 to $49 flat per claim. Scaling fees by recovery amount on US refunds is structurally overpriced because the federal rule is unconditional.

• ›

  EU261 or UK261 cash compensation: 25 to 27 percent direct settlement, 35 percent legal escalation, 45 percent national enforcement body filing.

• ›

  Montreal Convention documented loss: 25 to 35 percent of net recovery. Loss documentation requires more service work than fixed cash compensation.

• ›

  Codeshare resolution: typically no separate fee. The platform should identify the right respondent per jurisdiction at intake.

• ›

  Multi-passenger or family bookings: most services price per passenger. Bundle pricing through one platform is usually cheaper than separate filings.

For the math on flat fees vs percentages, see why a flat fee beats a percentage for most US flight claims and travelstacks vs airhelp: flat fees vs percentages.

1. 1

   Map all jurisdictions your trip touches: US DOT, EU261, UK261, Montreal Convention.

2. 2

   Identify the operating carrier on each leg (codeshare resolution).

3. 3

   Estimate per-jurisdiction recovery using the calculator pillar.

4. 4

   Pick a platform that files per jurisdiction in parallel, with per-jurisdiction pricing.

5. 5

   Confirm Montreal Convention stacking is filed automatically when documented losses exceed EU261 or UK261 cash entitlement.

6. 6

   Confirm escalation paths to DOT (US), CAA (UK), DGAC (France), Luftfahrt-Bundesamt (Germany), or other relevant NEBs.

7. 7

   For airline insolvency risk on the carrier, confirm ATOL or supplier default insurance routing as a fallback.

TravelStacks runs parallel filings per jurisdiction from a single intake, with $19 flat for US DOT refunds and percentage tiers for EU261, UK261, and Montreal Convention recovery. For your starting point, use the how much delayed flight worth calculator pillar. Start a claim.