[Joan]

It varies dramatically from one airline to another.

Delta typically (but not always) allows this, but it’s rarely worthwhile on Delta (every now and then there’s a great cash upgrade price, but it’s not terribly common.)

Several airlines will offer relatively cheap upgrades near the day of the flight or allow you to bid for an upgrade if they still have several open seats left in a premium cabin.

However, if the cabin is nearly sold out, then they won’t do that, so it will vary from one day to the next.

Each airline has their own policies for this and whether it’s worthwhile or if it’s available at all varies a lot both by airline and from one flight to another.

[Marjorie]

Short answer- yes, but usually on short-haul commuter flights within the US.

[Edy]

I can only speak for Delta – when you make any changes or cancel a ticket, you automatically lose any upgrade points or dollars.

So I never opt for an upgrade until right before the flight.

[Alessandra]

On KLM, they typically will allow you to bid on upgrades.

I had a KLM economy ticket for ORD-AMS that I booked on miles and when I checked in, there was an option to bid on a paid upgrade to business.

It was only $500 I think.

But your mileage may vary.

Depends on the route, airline, etc.

[Nathan]

I’ve done this with Delta a few times but rarely does the math work.

Usually, at least with Delta, the First Class upgrade price is ridiculous compared to just booking First Class in the first place (sometimes the upgrade is more than just buying a First Class ticket… why? Delta).

Once in a great moon though I can book a points ticket in Main Cabin or Comfort Plus and then I keep checking the First Class cash upgrade and will find a sweet deal. But let me also say those deals don’t last.

The last time I did this on an MSP to SEA flight, I was able to snag a cheap upgrade but after I bought mine it drove the algorithm to push the price 300% higher.

[Helena]

It varies a lot.

I travel on United a lot and what I end up usually having to do is book the economy award, then also book a business award (even if the points are crazy high).

As the date approaches, sometimes the business award becomes lower priced then I’ll do that (and cancel the economy award).

To be honest, I’ve had basically zero success while using United mileage plus points for either Swiss, Lufthansa or United to pay for an upgrade.

There are way too many people in line ahead of lowly ole me (people who paid cash already, have some status, etc and are upgrading from a cash ticket).

United Mileage Plus website will outline their specific complex upgrade policies if you want to read at least that carrier.

By the way, I’ve also had zero success upgrading when my original flight was on points with Air France, British Airways, or Lufthansa — could be just me and my luck.

I have though, often had luck upgrading from an original cash ticket on those carriers.

They will email an upgrade offer or they will notify you at the point of check-in.