The end of the year is a good time to check up on a number of things: emergency kits, retirement plans and so on.

Here are four items that frequent travelers should potentially add to their end-of-year housekeeping list.

1. Check your airline mileage accounts. Many airlines have mileage expire after a certain period of inactivity, usually 18 months. Even if you’re not planning to fly there are easy ways to get at least a few miles that will keep the account active. (Online shopping at one of thousands of stores can be the simplest, or even just buying 500 miles.)

2. Check your passport expiration date. It might be sooner than you think.

This one isn’t just hyperbole either, as in the past year I’ve had several clients make mistakes — one discovering the day before a trip planned six months prior that his passport was a few months out of date; another discovering at the airport his passport expired in a month, not a year and a month, which meant the airline wouldn’t let him on the plane to Costa Rica.

3. Check how many blank pages are left in your passport. A lack of space to stamp an extra visa IS enough in some cases for denied entry. (South Africa, for example, can and does deny entry for anyone with less than two blank pages.)

It isn’t difficult to get extra pages added to an existing passport, although it does cost $82, and does require processing time.

4. Start thinking about 2013 holiday travel now. This only applies to those who like to get away for holidays, especially somewhere warm. But if you are considering a trip for Thanksgiving or the end of 2013, start thinking about it now. Flights open up 331 days in advance and cruise and hotel bookings are already open. Such travel probably still won’t be inexpensive, but at least you have a better chance of getting exactly what you want.