Gear Prudence: I’m getting a tax refund. Thanks, IRS! It’s about $1,000, and I’m trying to decide whether I should use it to pay off some credit card balances or whether I should buy a bike with it. Here’s why I think the bike would be a good idea: I could start bike commuting and then use all the money I save each month to pay down my credit card over time. After a few months, it’d be the same as the tax refund, and then after that, I’d have even more money to pay down my debt. This seems like a no-brainer, but my friends keep telling me that it’s a bad idea. What should I do? —Definitely Expecting Biking Treasure

Dear DEBT: GP isn’t consulted very frequently on matters of personal finance, but faced with your unexpected windfall and your desire to procure a bicycle, you’ve come to right place. Over the years, GP has saved thousands of dollars through daily bike commuting, which have then been subsequently frittered away on superfluous bike accoutrements, but let’s not dwell on that. You might not be happy with this advice, which is to pay off the credit card. There are two reasons why, the first one of which should be quite obvious: Credit card companies charge interest, and each month your outstanding balance accrues more of it, which ultimately works against your goal of eventually paying it off. Faced with the opportunity to reduce the balance (and the amount of interest it accumulates), it’s a financially prudent decision to do so. This is a boring answer, but the right one.

But let’s unpack this theory about how buying a bike with your windfall will lead to a brighter financial future. Indeed, you are correct: Commuting by bike would save you money in the future and you could use this money to pay down your debt over time. Here’s the thing that a lot of people forget: Buying a bike and actually bike commuting are two entirely different things. So many bikes languish unused after folks said to themselves “I should bike commute!” only to try it sporadically or decide that it’s really not practical for them. That means the anticipated savings from bike commuting are never realized, and not only did you not pay down your debt when you had a chance, you aren’t saving any additional money from bike commuting, either.

Honestly, it feels weird to say “don’t buy a bike,” so that’s not exactly the advice. It’s buy a cheap bike, or buy a Bikeshare membership, and use the rest of the money to pay off the credit cards. If you take to bike commuting, then even better. That’s even more money that you can save down the road. Also, fix your W-4—you’re withholding too much. —GP

Gear Prudence is Brian McEntee, who tweets at @sharrowsDC. Got a questions about bicycling? Email gearprudence@washcp.com.