The secret to getting a cheap flight upgrade

So then, more out of curiosity than anything else, I wondered if it was possible to upgrade with frequent flyer points. The woman at the desk said yes, and went into the computer to find out how many that would set me back. The answer? 10,000 miles, plus $83 in taxes.

That's such a ludicrously good deal that I wanted to declare my undying love for the woman at the check-in desk. But there was a catch. She wasn't authorised to make such a transaction – it had to be done by phone.

So I phoned up the frequent flyer club, explained the situation, gave my credit card details and authorised them to take 10,000 miles out of my account. I had 140,000-odd in there, so this seemed a brilliant investment of a small chunk of them. Within a couple of minutes, I'd got the Upper Class boarding pass in my grateful paws.

How to upgrade on the cheap

The obvious lesson from this is to always ask about the cost of an upgrade when checking in or dropping off your checked in luggage. The worst that can happen is that they give a price so absurdly high that you descend into fits of laughter. But it may be surprisingly cheap – and this is to do with how airline frequent flyer schemes work.

This instance was Virgin Atlantic, but most other schemes work in a similar way. Limited numbers of seats in each class are set aside for frequent flyer redemptions on most sites. Sometimes these are snapped up very quickly, sometimes they remain available until right before the flight due to lack of demand.

On other occasions, extra seats are released later on. Again, this tends to happen when the plane isn't full. So when you book, there may only be economy redemption seats available – but seats in higher classes may be released closer to your departure date. And upgrading to those newly released seats can often be bizarrely cheap – it's a quirk of most frequent flyer schemes that upgrading tends to be much cheaper than paying outright for a higher-class ticket.

The check-in agent may be able to alert you to this if you ask about it, but it's also possible to investigate independently a day or two before. Simply log into your frequent flyer account and go to make a dummy booking for the exact flight you're going to be on. If there's availability in the higher classes, there's a strong chance that you'll be able to upgrade for a relative pittance. Some airlines will allow you to do this online – others you'll have to phone.

It may take a few extra minutes while doing an online check-in, but if you want to turn left without it emptying your wallet, this is by far your best chance of making it happen.

See also: The perfect airline seat
See also: How to get an airline upgrade
See also: Why airlines are upscaling amenities for high-paying fliers