Airline money does not flow like retail money. A single passenger name record spawns an e-ticket, one or more EMDs for seats and bags, card captures through multiple acquirers, BSP/ARC remittances from agencies, and later a chain of ADMs/ACMs and involuntary refunds when schedules slip. If finance treats those artifacts as mere “booking data,” cash will drift, chargebacks will spike, and treasury won’t be able to explain why yesterday’s full flights didn’t translate into today’s bank balance. Treat the artifacts as ledgers—PNR, ET, EMD, and remittance calendars—and the system starts paying you back.
Start with channel truth. Direct dot-com and app sales look like normal card-not-present commerce, but even there payment design should reflect airline physics. Authorization at ticketing, not at browse; partial captures when ancillaries are added; final reconciliation at flown status. Rate-lock metadata belongs on every monetary event—fare capture, ancillaries, upgrades, refunds—so FX noise is arithmetic, not email. Cards carry the volume, but account-to-account rails matter now in core markets: SEPA Instant in the euro area for refunds that close complaints in minutes; Faster Payments in the UK for same-day goodwill after delays; Pix in Brazil to get out of the chargeback treadmill on domestic leisure; UPI-linked flows for India segments where approval rates on cards are volatile. “Pay by bank” converts better when you show passengers the exact arrival time and let them choose speed vs fee; the descriptor must read like your brand and route, not a processor’s nickname.
Agency cash sits on a different calendar. In IATA markets, BSP collects from accredited agents and pushes to airlines on a schedule; in the U.S., ARC mirrors that logic. Those remittances are not just totals; they are structured settlements against issued documents with tax bases, commission rules, and exchange rates that must survive into your GL. If you rely on PDF statements and keywords, DSO will float. Feed BSP/ARC hot files, remit calendars, and neutral fare/NUC math into a canonical store; give each agency PCC or location a virtual IBAN so off-BSP adjustments and debit memo recoveries land with deterministic references. When ADMs and ACMs start flowing—unreported coupons, under-collection of YQ/YR, wrong tour codes—the only way to keep peace with sales is to show the memo, the rule breached, the coupon affected, and the cash effect as one story in the agency statement.
Ancillaries changed the revenue mix and the refund burden. Seats, bags, priority, lounge, Wi-Fi—most ride EMD-A/E, and their payment life is not the same as the ticket’s. If you blend them, you’ll issue refunds you can’t defend. Keep ancillaries as first-class monetary objects with their own tax logic; tie them to segments and RBD; record whether they were consumed (seat sat, bag flown) and whether they are involuntary. When IROPs hit, an SSR OTHS/INVOL toggle and the reissue history should drive refund rights without agent creativity. Post-travel service recovery—meal vouchers, partial vouchers after cabin downgrade, goodwill miles—should be ledgered too; otherwise your chargeback desk will be trying to prove kindness with chat screenshots.
Fraud in air isn’t theoretical; it has a timetable. One-way international, short time-to-depart, high fare buckets, and midnight local time are where carders live. Devices, IP coherence, BIN/country match, and 3-D Secure on risk signals are basics, but the airline-specific levers matter more: refuse “instant issue + depart < 6h” without history; step up when an account adds multiple high-value ancillaries minutes after ticketing; treat multiple PNRs with shared phone/email and different cards to the same destination as one risk object. Your best disputes are the ones you never take: SCA exemptions used sparingly, descriptors that say “AIRLINE • CITY–CITY,” and a refund posture that returns to the original method quickly when service truly failed. When you do fight, the evidence pack must assemble itself: PNR, ET coupon status, DCS logs (boarded/no-show), SSR trail, reaccommodation record, and passenger communications.
Interline and codeshare cash is where “we were full” still doesn’t equal “we got paid.” IDEC/ICH proration rules decide who keeps what on multi-carrier itineraries; the delay between flown and cleared cash can be weeks. Finance needs two maps: which carriers and routes are net recipients vs payers, and which currencies and calendars those flows hit. The ledger must store coupon-level proration and the value date of ICH clears so treasury can ladder coverage on predictable USD outflows and leave EUR-denominated legs alone. If you’re moving to NDC with airlines or as one, remember that many of the old EDIFACT settlement comforts vanish; build settlement logic that carries offer/Order IDs, service IDs, and tax breakdowns natively and reconcile them to money, not to marketing slides.
FX is not an afterthought in fares. Fare construction still dances around currency of commencement of travel and NUC conversions; acquirers settle in their chosen currency; BSP/ARC remits in another; sellers quote in a third for conversion. Discipline beats bravado: natural hedge where possible (spend local station costs, airports, and catering from local inflows), short-dated forwards on net exposures where you cannot, and small buffers in high-velocity wallets to absorb weekend and bank-holiday drift. Every cash event—BSP receipt, acquirer batch, refund batch, ICH net—gets a rate, a source, and a timestamp. When auditors ask why EUR revenue ticked down on a week of USD-denominated fuel surcharge moves, the answer should be a waterfall, not a thesis.
Corporate and TMC flows have their own rails. Lodge cards and UATP settle smoothly when your back-office preserves the line-level link between client, policy, and charge; virtual cards issued by OTAs require respect: don’t try to capture tips or odd ancillaries against an OTA VCC beyond its funded envelope, and don’t switch the currency unless the contract says so. For direct corporate, account-to-account invoicing with remittance advice reduces ambiguity; early-pay discounts on dispute-free accounts buy loyalty and lower cost of funds more reliably than another marketing campaign.
Refunds are where reputations go to heal or to die. Airline refunds are complex because “voluntary” and “involuntary” are not feelings; they are document states driven by timetables, minimum connection times, and rule categories. Encode that into the booking system and the finance engine: a cancellation by the carrier inside a window creates a right to cash back to the original form within a promised SLA; a schedule change beyond a published threshold allows reroute or refund; customer-initiated cancels on non-refundable fares create EMD residual or fees per rule. Publish the clocks to passengers and then beat them using instant rails where you can. The number of chargebacks you will never see is proportional to how close “we’re processing it” gets to “the money is back now.”
Data and reconciliation finish the job. Money wants identity: order/PNR, eticket number, coupon numbers, EMDs, agency IDs, acquirer batch IDs, ICH reference, BSP/ARC period. Store amounts as integer minor units with ISO currency codes; stamp rate, source, and time on every entry; make every external call idempotent. Ingest ISO 20022 bank statements; assign virtual accounts per market, agency cohort, and acquirer so inbound funds land with self-describing references. A good variance engine doesn’t say “off by €12,403”—it classifies: acquirer fee drift, FX spread, partial batch, BSP short-landing, ICH timing, ADM netting. Owners clear categories, not mysteries.
The dials worth watching are not dramatic but they move margins. Approval rate by corridor and method; cost per successful transaction including FX and ops minutes; time-to-refund median and 95th percentile by rail; chargeback-to-sales and win rate on the short-haul “no show” pattern; BSP/ARC dispute aging and ADM ratio; ICH settlement lag; ancillaries attach and consumption rates with the cash delta between sold and flown; FX cost as basis points of flown revenue and of refunds; auto-match rate and manual minutes per thousand transactions. When commercial and finance stare at the same dials weekly, “we had a great load factor” turns into “we banked the cash at predictable cost.”
There is a clear role for a payments intermediary in this stack. If you need multi-currency accounts per market, virtual IBANs for agencies and OTA cohorts, local instant rails for refunds that defuse complaints, and deterministic reconciliation across acquirers and BSP/ARC—without stitching a dozen bank relationships—bring in a specialist. A provider like Collect&Pay earns its place when they deliver corridor breadth, predictable uptime, failure-handling that doesn’t embarrass you on social, and line-level fee/FX transparency your auditors will sign.