Should you use miles to book holiday travel?

A chill is in the air — and running down the spines of those looking for flights during the holidays.

Almost half (45%) of Americans plan to spend money on flights and hotels as they travel for the holidays in 2019, according to a nationally representative survey commissioned by NerdWallet  and conducted online by The Harris Poll among 2,050 U.S. adults. And about a third (32%) of these holiday travelers plan to use credit card points and frequent flyer miles to cover some or all of their expenses.

But is using points and miles during the holidays a good idea? Or is it a waste of your hard-earned travel rewards?

In the past, many airlines simply did not allow award travel during the holidays, deeming the second half of December “blackout dates.” As more airlines have adopted dynamic award pricing, they’ve opened up flights during these dates — but raised the number of miles needed to book them.

The question is, do these higher award fares match the high cash fares during the holidays? And if so, is booking them a good use of your miles?

To find out, we compared award and cash holiday fares across six domestic airlines (Alaska, American, Delta, JetBlue, Southwest and United). That is, we searched for flights using miles and flights using cash, then determined the “cent per mile” value and compared that to our regular mile valuations .

The short answer: In general, late December flights aren’t a bad use of miles, but it depends on the airline.

What we did

We compared award and cash fares on six airlines for two date ranges:

• Weekend to weekend, Dec. 21 or 22 through Dec. 28 or 29 (whichever dates had the lowest fares).

• Christmas to New Year’s (“holiday to holiday”), Dec. 24 or 25 through Dec. 31 or Jan. 1. These dates can sometimes have lower cash and award fares.

We collected data on two routes:

• Round-trip flights from Los Angeles to New York (JFK or EWR). This route was served by all six airlines.

• Round-trip flights from the airline’s hub to a small airport (e.g., Denver to Bozeman, Montana, for United).

Obviously, these dates and routes don’t cover every possibility. But they do offer a representative, snapshot view of holiday award flight booking. (And we’ll explain below how to check your own dates and routes.)

What we found

Cash fares

We found an average cash price of $450 per round-trip flight across all dates and routes. Weekend-to-weekend fares cost $515 on average, while holiday-to-holiday fares were $385. As expected, bookings on the holidays themselves offered considerable cash savings ($130, on average).

Award fares

This is where things get interesting. Round-trip award flights cost 42,582 miles on average — 49,606 miles for weekend-to-weekend bookings, and 42,587 miles for holiday-to-holiday travel. Here’s the full breakdown comparing cash and mile costs:

The “cent per mile” column is the important one here. That’s how much value (in cents) you’re getting for each mile used. As you can see, the results are fairly uniform across the different date ranges.

Basically, the takeaway is: If you’re traveling on peak days, you’re going to spend a lot (whether it’s miles or dollars). And if you’re traveling on the holidays themselves, you’ll spend a bit fewer of either, though miles may offer slightly less value on these dates.

Differences among airlines

Not all miles are created equal, however, and the results were more varied when broken out by airline.

As you can see, Alaska and Southwest led the pack in terms of offering the best cent-per-mile value during the holidays. But what’s more important to pay attention to is the difference between these holiday valuations and our standard domestic mile valuations. This shows which airlines’ miles offer a particularly good (or bad) value when used during the holidays.

For example, Southwest’s 1.5 cents per point value during the holidays is in line with the usual value we give to Rapid Rewards points. Ditto for Alaska. But for the routes we looked at, United and Delta miles offer considerably less value for holiday travel than can be found at other times.

Bear in mind that these values are all estimates. What really matters is which currency (cash or miles) makes more sense for you to spend on flights. If spending 40,000 miles feels more manageable than adding another $400 charge to your credit card, then by all means use your miles.

Try it for yourself

The best way to determine whether using miles makes sense for your holiday plans is to compare cash and award fares for the dates and routes you’re considering. Here’s how to do it:

1. Search for cash fares using a flight search engine like Google Flights.

1. Search for award fares in the program(s) where you have enough miles (at least 20,000 miles for most round-trip routes).

1. Subtract the fees for the award flight from the cost of the cash flight. Then divide this amount by the cost of the award fare (in miles) and multiply by 100.

1. If the result is greater than or equal to the NerdWallet valuations shown above, you’d be getting good value from your miles. If it’s less, consider paying cash.

The bottom line

Knowing when and how to use your frequent flyer miles is one of the most basic — and most difficult — travel decisions. And the high cost of holiday travel only raises the stakes.

Overall, we didn’t find a huge difference in the value of using miles during the holidays versus other times. Some airlines like Southwest and Alaska offered award fares in line with their normal values. Others, like Delta and United, offered less cent-per-mile value during the holidays.

The best way to tell if it makes sense to use miles to book holiday travel is to make your own comparison for the ticket you’re considering. It’s easier than you might think .

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The article Should You Use Miles to Book Holiday Travel? originally appeared on NerdWallet.