You Can Now Buy United Miles With An 85% Bonus….But Should You?

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Barely a day goes by when one of the major airlines doesn’t have a points sale in progress so we’re living in an age where “standard” prices are only really placeholders while the airlines get ready for the next discounted offering.

American launched its sale (with a twist) a few days ago and now United is offering a bonus of up to 85% on its miles through 19 December 2018.

Link to the promotion page

a man with a blanket blowing sparklers

United’s Miles Sale – Headline Rules

  • Promotional offer valid until 11:59 p.m. CT on December 19, 2018.
  • Miles are available in increments of 1,000 up to a maximum of 81,000 miles.
  • Bonuses will be calculated on a per transaction basis only. The bonus amount applicable to a transaction is shown in the chart. Transactions may not be aggregated to calculate the bonus.
  • Bonus Miles will generally be credited to the recipient’s MileagePlus account when the transaction is complete; provided that certain transactions may take up to 48 hours.
  • Bonus miles count towards the 150,000 mile annual limit per account.
  • Purchase up to 150,000 miles per account per calendar year.
  • Credit card will be billed immediately upon purchase.
  • Mileage rates and other fees and offer terms are subject to change.
  • Pricing is only available for purchases made through
  • Miles are nonrefundable.
  • Purchased miles do not count toward MileagePlus Premier® status.
  • All MileagePlus Program Rules and terms and conditions apply.
  • GST/HST is charged to Canadian residents. processes all of United’s mileage sales so you won’t earn an airline/travel bonus though your credit cards – make sure to use the card whose points you value most or a credit card on which you have yet to hit a sign-up bonus target.

For the full T&Cs please use this link and have your MileagePlus number to hand

the tail of an airplane

Buying Miles – The Math

Here’s the promotion as I’m seeing it in my MileagePlus account:

  • Buy 6,000 – 15,000 miles and get a 30% bonus
  • Buy 16,000 – 24,000 miles and get a 50% bonus
  • Buy 25,000 – 81,000 miles and get a 85% bonus

What that means in more useful terms is this:

  • Buy 6,000 – 15,000 miles at a cost of ~2.89 cents/mile
  • Buy 16,000 – 24,000 miles at a cost of ~2.50 cents/mile
  • Buy 25,000 – 81,000 miles at a cost of ~2.03 cents/mile

To buy United MileagePlus miles at the best rate you would need to buy between 25,000 and 81,000 miles and, within this band, the cost per mile remains constant (more or less).

If you were to buy the full 81,000 miles allowed in this sale it would cost $3,047.63….

a screenshot of a phone

…and you would net 149,850 miles after accounting for the bonus.

That works out to be approximately 2.03 cents per mile.

Buying just 25,000 miles would still qualify you for an 85% bonus so the cost/mile remains the same – you don’t need to buy the maximum allowable number of miles to get the best rate.

United Airlines Polaris Business Class

Should You Miles In This Sale?

If you’re planning on hoarding the miles the answer to that question is simple – no!

Assuming you’re not planning on buying miles just to sit on them here are a few things to note:

  • At 2.03 cents/mile this is not as good as the September sale which saw miles on sale from 1.88 cents each but this is still one of the better sales United has published this year.
  • There’s no scope for earning any extra credit card points/miles here (from bonus category spending) as the transactions are processed by and will earn just 1 point/mile per dollar.
  • I value United MileagePlus miles higher than I value the miles issued by either Delta or American but I still value them considerably lower than the 2.03 cents selling price that’s on offer right now.

What this means is that unless I can see a very specific and immediate use for the miles (which would save me money) I wouldn’t buy miles in this sale.


My situation isn’t always the situation a lot of people find themselves in as I can be more flexible than most when it comes to booking flights.

This means that I don’t often find myself in a position where I’m forced to purchase fares that cost considerably more than I’m normally happy to pay.

A fact of life is that premium cabin fares are usually expensive (often very expensive) so, if you absolutely have to fly when fares are not in your favor, miles may help you save a considerable amount of money (as long as you can find award availability that works for you).

Here’s what I mean:

Roundtrip non-stop Business Class fares between San Francisco and Paris for March (on any airline) are currently pricing at over $4,000….

a screenshot of a calendar

…..but, if you can find a Business Class United Saver award for dates that work for you, it would set you back just 120,000 miles + taxes.

120,000 miles in this promotion will cost approximately $2,436 so, even when you add in the taxes that you’ll have to pay out of Paris, you should still be able to make substantial savings.

Business Class fares on United’s Star Alliance partners are more expensive (140,000 miles for a roundtrip booking) so to book one of those with miles bought in this sale would cost ~$2,842….but that can still represent a huge saving if you can find award availability.

This doesn’t just work for transatlantic routes, the savings across the Pacific can be even better.

If you take the example of a roundtrip non-stop Business Class fare between San Francisco
and Tokyo in May the fares start at over $6,000:

a screenshot of a calendar

If you’re lucky enough to find a saver award on United it will cost you 140,000 miles + taxes and, in this sale, the miles would cost ~$2,842.

A Star Alliance award would cost 160,000 miles on this route so you wouldn’t be able to buy all the miles you need in this sale but, assuming you had a little over 10,000 miles already in your account, the extra miles needed to book the award would cost you around $3,047.63.

Taxes on this route would be minimal so the savings could be fantastic….as long as you can find award availability in the first place – that’s key!

Bottom Line

I can think of two scenarios in which buying miles in this promotion may be good idea:

  1. You need to top up a MileagePlus account with a small number of points to get you enough miles to book an award.
  2. You need to book an award to save money over a cash fare that you would otherwise have to buy.

If you fall into one of those two categories then here’s a link to buy some miles, if you don’t then this promotion is probably not for you.

Remember that this sale ends at 11:59pm CT on 19 December 2018

Most importantly: Do your research before you buy any miles and make sure the award you want to book is actually available.

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