I’m obsessed with the latest technology. I buy lots of gadgets.

However, my biggest tech obsession is new software. Many days, I download apps to my phone, install apps on my MacBook, and sign up for new software services.

I keep up with what’s happening by reading a bunch of blogs and keeping a close eye on Hacker News and Product Hunt.

Many of the software services I sign up for offer a free trial. I’m all about a free trial. I sign up for stuff constantly.

However, sometimes these services require a credit card for the free trial, or they require you to pay (crazy, I know) for use of the service. That doesn’t stop me. I sign up regardless.

But when I give them a credit card number, I worry about remembering to cancel if I decide that I don’t want to keep my account. I hate to have to track all these accounts, but I know that if I’m not careful, I’ll get billed month after month for something I’m not using.

How to Protect Yourself From Unwanted Ongoing Charges

Citibank to the rescue (and probably some other credit card companies as well).

Citibank allows you to create something known as a virtual account number, or VAN for short. A virtual account number is a temporary virtual credit card number that is linked to your actual credit card number.

Many folks use these VANs when they’re dealing with suspicious online merchants for a single purchase. Let’s say you’re buying a scented candle for your Aunt Charlotte from some flake you found online. You aren’t sure you trust the flake with your credit card number, so you get a virtual credit card account number from Citi, and it’s good for one transaction. You give it to the flake, pay for your candle, and the card is now dead. Perfect: there’s no risk of the flake taking your card number and running off to Macau for the weekend.

Well, what if you used a VAN for a software service?

It’s the perfect solution. You use it, and the service charges you the fee once. Then, when it’s time to renew, the company runs your card and it gets declined. Excellent. Now it’s got to hunt you down for your new credit card number. The burden to cancel has shifted. Problem solved.

You can do all sorts of things with the Citibank VANs. You can determine how long the card is active, and you can impose a preset spending limit.

Citibank explains it all in this video.