There are four ways to upgrade to business or first class, and the airline decides which ones it will sell you: cash after booking, miles, a certificate, or a bid. A fifth route, the complimentary elite upgrade, costs nothing and is the hardest to control.

Three airlines publish their rules in enough detail to plan around: Delta, JetBlue and Emirates. We read all three on September 12, 2026. Five others blocked us entirely, and that's its own section at the end, because a rule you can't read is a rule you can't rely on.

The Four Routes, and What Each One Costs You

Cash after booking is the simplest and usually the worst value, with one exception: it can earn status credit. Delta says paid upgrades "will earn Medallion Qualification Dollars (MQDs) and applicable mileage accruals," while "Complimentary Upgrades will not earn additional MQDs."

Miles work when the cash price is high and your balance is idle. The catch is always fare class, not availability.

Certificates are the elite instrument, and they outrank the free upgrade queue.

Bids let you name a price, which sounds friendly and is mostly a way for the airline to find your ceiling. You give up flexibility when you win.

Delta: Every Route Except a Bid

Delta publishes the most complete set of rules of the three, and it runs no bid program on any page we could find.

Paid, after you book. On Delta's seat support page, the window is exact: "Any time after a ticket is issued until 90 minutes prior to departure or until the check-in window has closed, customers can purchase an upgrade to Delta One, Delta Premium Select, Delta First or Delta Comfort if the product is available on their flight."

Three rules decide whether you'll see the offer at all. Basic fares are out: "Delta Basic experience customers may not purchase an upgrade." The whole reservation has to move together, since "all customers in the reservation must upgrade for the selected flight." And the itinerary must be "wholly operated by Delta or Delta Connection."

If your plans change, the money doesn't come back as money. Delta says you "may receive an eCredit for the value of your paid upgrade if you cancel your flight before the 24-hour check-in window opens."

Miles. On Delta's upgrade page, any member can use miles at or after booking, but self-service is limited: "You can only upgrade with miles on delta.com or the Fly Delta app if your entire reservation is operated and marketed by Delta."

Then there's the instrument most people never touch. Mileage Upgrade Awards "may be redeemed for fixed mileage amounts according to area of travel and are only valid with certain fare classes," must be "booked through a Reservations Specialist," and can be done up to 24 hours before departure. They work on Delta, Virgin Atlantic, Air France, KLM and Aeromexico flights, and Delta lists the qualifying fare classes for each.

Certificates. Global and Regional Upgrade Certificates come through Choice Benefits at the top tiers, and Delta's current page gives them real weight: they "have a higher priority than Medallion Complimentary Upgrade requests."

The current rules are more generous than older pages suggest. Certificates "can be used for yourself and/or multiple companions," and "can also be used on Award Travel tickets and Miles + Cash tickets on Delta-operated flights, Pay with Miles tickets, Companion Certificates." Delta ties expiry to the Medallion Year: certificates from the 2026 selection "must be booked and flown by January 31, 2027."

One operational detail worth knowing before you waitlist: "One Upgrade Certificate can put you on a single waitlist or multiple waitlists," but "your upgrade will only clear off of ONE waitlist and will be based on the FIRST seat that becomes available." If nothing clears, "your certificate will be returned to your account for you to use on a later flight."

A caution on numbers. Delta serves an older certificate page carrying 2017 dates that contradicts the current one on companions, award tickets and expiry. The per-tier certificate counts appear only on that stale page, so we're not repeating them here.

Complimentary, for Medallions. All Medallion tiers get unlimited complimentary upgrades to Delta First and Delta Comfort, plus domestic Delta Premium Select and domestic Delta One, on Classic or Extra fares. Outside the US 50, Delta says complimentary upgrades to Premium Select or Delta One are "not permitted."

The queue order is published: "Medallion Tier is the most important factor in upgrade clearance priority, starting with Diamond Medallion Members, then Platinum, then Gold and then Silver," with MQDs earned this year as the tiebreak, grouped in increments of 100.

Check your profile defaults once. Delta says that if you've never set upgrade preferences, you're opted in for Delta First, domestic Premium Select and domestic Delta One, but "opted out of automatic upgrades to Delta Comfort."

JetBlue: the Bid, Explained Properly

JetBlue's upgrades page documents its bid program in more detail than most airlines manage, and the details are the whole story.

Bidding is free until you win. "Submitting an offer is free. Your card will only be charged if your upgrade is confirmed." If the offer isn't accepted, "No charges will be applied. The original booking and services remain unchanged."

You can change your mind, until you can't. "You may submit, modify, or cancel your offer up to 30 hours before scheduled departure, provided it has not already been accepted," with a footnote that it's 25 hours on select routes.

Winning locks you in. "Once accepted, the upgrade is final and may not be changed, transferred, retained for later use, or applied to another flight," outside narrow refund exceptions such as the airline cancelling or an aircraft change.

Everyone on the booking comes along. "If multiple travelers are on the same booking, upgrades will apply to all travelers," and "Bookings may not be split for the purpose of partially upgrading a party." The price is per customer.

It's per segment. Asked whether benefits apply to the whole journey, JetBlue answers: "No. Benefits typically apply only to the upgraded flight segment, not the entire itinerary."

If you'd rather not bid, JetBlue also sells an Instant Upgrade, which "allows you to secure an upgrade for the selected flight segment immediately at a fixed price, without bidding." It's non-refundable too.

One bonus worth factoring in: a confirmed Mint upgrade comes with BlueHouse lounge access "up to 3 hours before your departing flight from JFK or Boston."

What JetBlue doesn't publish on that page: any way to upgrade with TrueBlue points, and any complimentary elite upgrade rule. Its Mosaic and Move to Mint pages returned errors to us, so treat both as unpublished rather than nonexistent.

Emirates: Miles, With the Rules in the Program Document

Emirates' marketing pages are thin, but its Skywards Programme Rules are the most precise document any of these three airlines publishes.

The deadline. "Upgrade Reward requests must be made by Members at least six hours prior to departure." Instant upgrades are allowed at check-in, and on board only for some: "Subject to availability, Platinum, Gold and Silver Members may redeem Skywards Miles for Instant Upgrades on board." Blue members aren't on that list.

Your fare decides everything. Emirates says plainly that "the fare brand you choose makes a big difference when it comes to upgrade eligibility." Special fares are "Not eligible for upgrades." Saver fares "can only be upgraded at online check-in between 48 and 6 hours before departure" and cost more miles. Flex and Flex Plus can upgrade any time up to six hours out, for fewer miles.

Taxes are cash. "All taxes (including airport and/or government taxes) where applicable are the responsibility of a Member and must be paid prior to the issuance of the Upgrade Reward ticket."

Cancelling is unusually painless. "No fees apply for cancellation of Upgrade Rewards."

But you earn on the fare you bought. "Members will earn Miles as per the original ticketed class of travel. No additional Miles will be awarded with respect to any Instant Upgrades or Promotional Upgrades used." An upgrade buys you the seat, not the earning.

Emirates also runs an auto upgrade subscription, processed "between 60 days and 48 hours from departure," which only fires if there are seats for everyone on the booking and you hold enough miles at that moment.

Our Emirates upgrade guide goes further into the miles pricing.

The Five Airlines We Could Not Read

This is the honest part. Every URL below was tried repeatedly on September 12, 2026.

  • American: every aa.com upgrade page returned HTTP 403 "Access Denied". Systemwide upgrades and Loyalty Choice Rewards are unsourced here. Our older American upgrades guide covers what we documented previously.
  • United: every united.com URL returned no response at all, including the PlusPoints page.
  • British Airways: every britishairways.com URL timed out with zero bytes, so its Avios upgrades and Upgrade Offers bidding are unsourced.
  • Lufthansa: every lufthansa.com locale and miles-and-more.com returned a 403 block page, so myOffer bidding is unsourced.
  • Alaska: alaskaair.com returned HTTP 200 but served a JavaScript shell with 49 characters of readable text. Gold Guest Upgrades are unsourced. The one thing the page titles do confirm is that Mileage Plan now carries Atmos Rewards branding, which matches what we found writing our status match guide.

Figures for all five circulate widely. We're not reprinting them, because we couldn't read them at the source.

A Quick Way to Decide

Start with one question. Is the seat worth real money to you on this flight?

If the answer is no, stop. Take the free upgrade if it clears and enjoy the flight either way.

If the answer is yes, the next question is what you hold. Miles and certificates cost you nothing extra today. Cash does.

Then check the clock. Delta cuts off paid upgrades 90 minutes before departure. JetBlue locks bids 30 hours out. Emirates wants six hours, and less if you hold a Saver fare.

Last, check your fare. This is the step people skip. A Basic fare on Delta blocks every route, paid or free. A Special fare on Emirates does the same.

Do those four checks in order and you'll know your options in about a minute.

What About the Middle Seat Problem

One more thing worth saying, because it catches families.

Two of these airlines upgrade the whole booking or none of it. JetBlue says bookings "may not be split for the purpose of partially upgrading a party." Delta says "all customers in the reservation must upgrade for the selected flight."

Emirates is the same on miles: "Upgrade Rewards can only be used if all passengers in a single booking redeem the applicable Upgrade Reward."

So if you're four people and you want one person up front, book separately or forget it. That decision has to happen before you buy the tickets, not at the gate.

Which Route to Take

If you want status credit, pay cash. Delta is explicit that paid upgrades earn MQDs and free ones don't. On a year where you're chasing a tier, a paid upgrade does two jobs.

If the cash price is silly, use miles, and check your fare class first. Every miles rule here turns on fare brand or booking class, not on whether a seat is empty.

If you hold certificates, use them before the Medallion Year ends. Delta's expire on a fixed date rather than rolling twelve months, and they outrank the free queue, which is exactly when they're worth the most.

If you bid, bid what the seat is worth to you. You can adjust until 30 hours out on JetBlue, and after that you're committed with no changes and no refund.

If you're relying on a complimentary upgrade, set your preferences today. Delta's defaults leave you opted out of Comfort upgrades, and the queue is decided by tier then by MQDs, not by when you checked in.

For where these cabins are worth chasing at all, our Delta SkyMiles program guide covers the redemption side, and our Delta One lounge guide covers what the front cabin gets you on the ground.

This article contains affiliate links. If you apply through our links, we may earn a commission at no cost to you, which helps us continue sharing points and miles strategies with the community.

Sources

  1. Delta Air Lines, seat and upgrade support page (read 2026-09-12): post-purchase upgrades until 90 minutes before departure or the close of check-in, Basic fares excluded, whole reservation must upgrade, wholly Delta or Delta Connection itineraries, eCredit rather than cash refund, paid upgrades earn MQDs while complimentary upgrades do not
  2. Delta Air Lines, upgrades and more with miles (read 2026-09-12): miles upgrades at and after booking, self-service limited to wholly Delta-marketed and operated reservations, Mileage Upgrade Awards booked through a Reservations Specialist up to 24 hours before departure with fare class lists for Delta, Virgin Atlantic and KLM
  3. Delta Air Lines, Medallion Choice Benefits (read 2026-09-12): Global and Regional Upgrade Certificates outrank complimentary upgrade requests, may be used for yourself and multiple companions, valid on award and Miles plus Cash tickets, and must be booked and flown by January 31, 2027 for 2026 selections. Per-tier certificate counts appear only on a stale legacy page and are deliberately not cited
  4. Delta Air Lines, Medallion complimentary upgrades (read 2026-09-12): all tiers eligible on Classic or Extra fares, no complimentary upgrades to Delta Premium Select or Delta One outside the US 50, clearance priority by tier then MQDs in 100 MQD increments, and the profile defaults that opt members out of Delta Comfort upgrades
  5. JetBlue, upgrades page (read 2026-09-12): bidding is free and charged only if accepted, offers may be modified or cancelled up to 30 hours before departure and 25 on select routes, accepted upgrades are final and non-refundable outside narrow exceptions, upgrades apply to everyone on the booking, benefits apply per segment, BlueHouse access on a confirmed Mint upgrade, and the fixed-price Instant Upgrade
  6. Emirates, Skywards Programme Rules section 14 (read 2026-09-12): upgrade requests at least six hours before departure, instant upgrades at check-in, on-board instant upgrades limited to Platinum, Gold and Silver members, taxes payable in cash, no cancellation fee for Upgrade Rewards, and miles earned on the original ticketed class
  7. Emirates, spend Skywards Miles (read 2026-09-12): upgrades from 7,020 Skywards Miles, Special fares not eligible, Saver fares upgradeable only at online check-in between 48 and 6 hours before departure, Flex and Flex Plus upgradeable up to six hours out for fewer miles
  8. American Airlines upgrade pages (attempted 2026-09-12): HTTP 403 Access Denied on every URL, so systemwide upgrades and Loyalty Choice Rewards are unsourced
  9. United Airlines PlusPoints and upgrade pages (attempted 2026-09-12): no response received, HTTP 000 on every URL and host variant, so PlusPoints rules are unsourced
  10. British Airways upgrade pages (attempted 2026-09-12): connection timeouts with zero bytes on every URL, so Avios upgrades and Upgrade Offers bidding are unsourced
  11. Lufthansa bid upgrade and Miles and More pages (attempted 2026-09-12): HTTP 403 block page on every locale, so myOffer bidding is unsourced
  12. Alaska Airlines upgrade pages (attempted 2026-09-12): HTTP 200 but a JavaScript shell containing 49 characters of text, so Gold Guest Upgrades are unsourced; page titles do show Atmos Rewards branding

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