Travel fares · Airline ancillary prices
Airline ancillary price tracking: bags, seats and fare bundles
Ancillary prices, meaning bags, seats, priority boarding and fare bundles, vary by route, date, market and how close to departure you look. Track them as a time series of their own so a trip's real cost can be compared, not just its base fare.
Pay per GB · No subscription · Prices in EUR, excl. VAT
- €2.00
- per GB on ARC Fast, excl. VAT
- −44%
- at 1 TB (€1.12 / GB)
- 185+
- countries, city targeting
- Never
- expires — no subscription
Written for
- Total-trip-cost comparison sites
- Airline ancillary and merchandising teams
- Consumer organisations researching airline fees
- Travel data journalists
The short answer
- Ancillaries are big money. IdeaWorksCompany and CarTrawler projected $148.4 billion in airline ancillary revenue worldwide for 2024, up from $117.9 billion in 2023.
- US airlines alone collected $7.3 billion in baggage fees in 2024, 2.9% of total operating revenue, according to the US Bureau of Transportation Statistics.
- In the EU, optional supplements must be shown clearly at the start of booking and accepted on an opt-in basis. The Court of Justice classifies checked bags as optional and hand baggage of reasonable size as, in principle, necessary.
- Collect from published fee pages and the public flow up to the extras step. Never enter invented passenger data, and never pay or hold a booking.
The problem
What goes wrong without the right IPs
Fee pages and the booking flow disagree
A carrier's fee page often lists a range or a 'from' price, while the flow quotes a route- and date-specific price. Both are useful, but they are different measurements. Label the source on every row.
The price depends on when the extra is bought
Many carriers price a bag differently at booking, after booking and at the airport. If you record a single 'bag fee' without the timing the carrier states, the comparison is meaningless.
Bundles hide unit prices
A 'plus' bundle that includes a hold bag and a seat does not tell you what either costs. Derive the implied price, bundle minus basic fare on the same flight, and store it as a derived field next to the observed one.
Allowances are not comparable out of the box
One carrier's hold bag is 20 kg and another's is 23 kg; cabin-bag dimensions differ by a few centimetres that matter at the gate. Normalise to a few standard products before you compare prices.
Seat maps sit behind personal-data steps
Some flows show seat prices only after passenger details have been entered. Do not invent passenger data to get there. Use the carrier's published seat price ranges instead, or a licensed source.
What to collect
What you can collect
- Ancillary type and allowance
- Hold bag 20 kg vs 23 kg, cabin bag dimensions, seat category. Comparisons need the unit.
- Price and its scope
- Per segment, per direction or per journey, as the carrier states it.
- Purchase timing
- At booking, after booking or at the airport. Often three different prices.
- Bundle price and inclusions
- With the basic fare on the same flight, from which you derive the implied unit price.
- Route, date and days to departure
- Many ancillary prices are dynamic, just like fares.
- Market and currency
- Fees differ by country edition. Keep the point of sale explicit.
- Source
- Published fee table or a flow step, labelled on every row.
- Observation time
- Fee pages change without notice; the timestamp is your audit trail.
How it runs
How a collection run works
- 01
Inventory the published fee pages
For each carrier and market, find the public pages that list bag, seat and service fees. Fetch them on the cheap rotating pool and diff them on every run. A change here is usually a policy change.
- 02
Sample the flow up to the extras step
On a sample of routes and dates, run the public flow with a sticky session, select the basic and bundle fares, and record what the extras step shows. Stop before any step that asks for personal data or payment.
- 03
Derive implied unit prices
Subtract the basic fare from each bundle on the same flight, and store the result next to the observed à-la-carte prices. Keep both; they answer different questions.
- 04
Normalise to standard products
Map every carrier's allowances to a few standard products, such as one 23 kg hold bag, one standard seat and priority boarding, and record any carrier that cannot be mapped cleanly.
- 05
Join to fares for total trip cost
Combine with airline fares and low-cost carrier fares on route, date and market. The output is a price per traveller profile, for example 'one adult with a hold bag'.
Setup
Recommended setup
Fee pages are static and cheap to fetch. Flow sampling is stateful and needs one residential exit per flow.
| Plan | Role | Session | Targeting | Price |
|---|---|---|---|---|
ARC Basic Rotating ISP | Published fee pages Static pages fetched per market and diffed. The cheapest pool per GB, and the country token gives you each edition. | Rotating | Country | €0.75 / GB €0.59 at 1 TB (−21%) |
ARC Fast Rotating residential | Flow sampling to the extras step Ancillary steps sit deep in the flow, so they take longer than a fare search. A longer hold keeps the whole flow on one residential IP. | Sticky, about 15 minutes per flow | Country | €2.00 / GB €1.12 at 1 TB (−44%) |
Prices are list prices in EUR, excl. VAT. Volume discounts apply automatically at checkout — full ladder on the pricing page.
Connect
One connection string per market
The country, city and sticky session are tokens in the username. Change the token, change the market; keep the session handle, keep the IP.
http://USERNAME_pool-arcfast_country-de_session-k3f9a1x2_sesstime-10:PASSWORD@proxy.arcproxies.io:8000Swap _country-de for any market you quote. The full grammar is on the residential proxies page.
Illustration
What a weekly ancillary panel costs
An illustration with round numbers — your pages, payloads and retry rate will differ. The arithmetic is the real price ladder.
Assumptions
- Routes sampled
- 200
- Fares per route (basic + one bundle)
- 2
- Markets
- 3
- Cadence
- weekly (4.3 a month)
- Weight per flow to the extras step
- 1.5 MB
- Fee pages
- 40 carriers × 6 markets, daily, 800 KB
- Bandwidth per month
- ≈ 14 GB
On ARC Fast
€28.00per month, excl. VAT
14 GB bought in one purchase at €2.00 / GB (list price).
The same 14 GB on ARC Basic: €10.50 at €0.75 / GB. Move down as soon as the cheaper pool holds up.
Ancillary tracking is light on bandwidth: depth per flow is high, but the panel is small. In practice the fee-page share runs on ARC Basic and the flows on ARC Fast.
Bandwidth never expires, so a bigger single purchase is only ever cheaper per GB. See the ladder.
In depth
Airline ancillary prices, in depth
How big airline ancillary revenue is
Ancillaries are no longer a side line. The figures below come from an industry estimate and from US regulatory filings, and they are a good way to size how much of a trip's price sits outside the fare.
| Measure | Figure | Source |
|---|---|---|
| Global airline ancillary revenue, 2023 | $117.9 billion | IdeaWorksCompany / CarTrawler |
| Global airline ancillary revenue, 2024 (projection) | $148.4 billion | IdeaWorksCompany / CarTrawler |
| US airlines' baggage fees, 2024 | $7.3 billion (2.9% of operating revenue) | US DOT / BTS |
| US airlines' reservation change fees, 2024 | $1.0 billion (0.4% of operating revenue) | US DOT / BTS |
IdeaWorksCompany attributed the 2024 increase largely to passenger growth and to market-share gains by low-cost carriers, which is why the fee series matters most on low-cost routes.
What EU law says about displaying ancillary prices
- Opt-in, at the start. Article 23(1) of Regulation 1008/2008 requires optional price supplements to be communicated clearly, transparently and unambiguously at the start of any booking process, with acceptance on an opt-in basis.
- Checked bags are optional; hand baggage is in principle not. In C-487/12 the Court held that carrying checked baggage may be an optional supplement, while hand baggage meeting reasonable weight, size and security requirements cannot be made subject to a supplement.
- Some fees are unavoidable. In C-28/19 the Court held that check-in fees are unavoidable where no free method exists, and that fees for paying with a card other than the one the carrier approves are unavoidable. Both belong in the initial price.
For research on fee practices, these rulings tell you which observations are price data and which may also be compliance findings. This is a description, not legal advice.
Normalising ancillaries so trip costs compare
Raw ancillary prices do not compare across carriers. Define a few traveller profiles your users recognise, such as 'cabin bag only', 'one 23 kg hold bag' and 'hold bag plus chosen seat', and price each profile per flight from the cheapest legitimate combination: à la carte or a bundle, whichever is lower.
Keep the mapping explicit. If a carrier's hold bag is 20 kg, either map it to the nearest profile with a flag or leave it out of that profile. Hidden assumptions in normalisation are the most common reason two 'total trip cost' tables disagree. The same profiles work for car rental and airport parking add-ons, the other big extras in a travel fare aggregation product.
Where to stop in the booking flow
The responsible boundary is the same everywhere: public, logged-out pages, and nothing that creates a booking, holds inventory or submits personal data. Bundle selection and fee summaries are usually visible before that boundary; seat maps sometimes are not.
Where a price sits behind passenger details, use the carrier's published ranges, or ask the carrier for a feed. Invented passenger data pollutes the airline's systems and does not belong in a dataset you want to defend. Collecting travel data responsibly covers the rest of the checklist.
Who uses ancillary price data, and what they need
| Team | Question | Cadence that fits |
|---|---|---|
| Total-trip-cost comparison | What does this trip cost with my bags? | Daily for top routes, joined to fares |
| Airline merchandising | Where are we priced against rivals per route? | Weekly panel, per market |
| Consumer research | Are fees displayed and charged as the rules require? | Snapshot studies with archived evidence |
| Data journalism | How have fees moved this year? | Monthly fee-page diffs |
Works with anything that takes a proxy URL
Playwright- Python requests / httpx
- changedetection.io
Crawlee- Docker
FAQ
Questions
Something not covered? Write to contact@arcproxies.io.
What are airline ancillary prices?
They are what an airline charges on top of the fare: checked and cabin bags, seat selection, priority boarding, fare bundles, changes and similar services. IdeaWorksCompany and CarTrawler projected $148.4 billion in global airline ancillary revenue for 2024.
Do airline baggage fees differ by route and date?
Often, yes. Many carriers price bags and seats dynamically by route, date and how close to departure you buy, and many charge differently at booking, after booking and at the airport. Track the price together with its route, date, market and purchase timing.
Must airlines show bag fees in the first price in the EU?
Not checked bags. The EU Court of Justice held in C-487/12 that checked baggage may be an optional supplement, which must be shown clearly at the start of booking and accepted on an opt-in basis. Hand baggage that meets reasonable requirements is in principle not chargeable as a supplement.
How do I compare bundles with à-la-carte extras?
Subtract the basic fare from the bundle price on the same flight to get the implied price of what the bundle adds. Then compare it with the sum of the same extras bought separately, and price each traveller profile at whichever is cheaper.
Can I collect seat prices without entering passenger details?
Sometimes. Where a seat map is only shown after passenger details, do not invent details to get past that step. Use the carrier's published seat price ranges, or ask for a licensed feed. Public, logged-out pages only.
How much bandwidth does ancillary tracking use?
Less than fare tracking. Flows to the extras step are heavier, around 1–2 MB in a browser with assets blocked, but panels are smaller. A weekly panel of 200 routes in three markets plus daily fee pages comes to about 13 GB a month in our illustration.
Sources & review
Last reviewed by the ARC Proxies team. Prices are read from the live catalog at build time.
- [1]IdeaWorksCompany: Airline ancillary revenue skyrockets to $148.4 billion worldwide for 2024
- [2]U.S. Department of Transportation (BTS): US airlines net profit was $6.7 billion in 2024, a decrease over 2023
- [3]EUR-Lex (Official Journal of the European Union): Regulation (EC) No 1008/2008 on common rules for the operation of air services in the Community
- [4]Court of Justice of the European Union: Press release No 127/14: Judgment in Case C-487/12, Vueling Airlines
- [5]Court of Justice of the European Union: Press release No 49/20: Judgment in Case C-28/19, Ryanair and Others v AGCM
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