Got a mortgage? Have you thought about paying it off early?

Seriously, this is something worth thinking about. It's actually a very good time to accelerate your mortgage payments. Sure, mortgage rates are low, but rates on bonds and CDs are a lot lower. Even the S&P 500's dividend yield is significantly lower, a lot lower than it was a couple of years ago.

So what? So this: When you pay off your mortgage early, you get a guaranteed return, in the form of thousands of dollars' worth of future interest charges that you never have to pay.

As sure financial bets go, that's a hard one to beat at the moment. But that's not the only benefit -- particularly if you pay it off before you retire.

A plan for a mortgage-free future
At this point, you're probably saying something like, "Dude, if I had enough disposable cash to pay off my mortgage now, I would have done it already." I hear that, and I have two answers for you. First, even paying some of your mortgage principal down now will be worth your while.

Imagine that you have $10,000 that you want to park somewhere safe for several years. My local bank pays 1.2% interest on a five-year, $10,000 CD. That's $120 a year, probably pretty typical of what you'd get at most banks right now.

Now consider: If you have a mortgage at 5%, every $10,000 of that is costing you $500 a year in interest payments. Sure, you can probably get that down a little bit if you refinance right now, at the cost of some fees and paperwork, but you aren't going to get it anywhere near 1.2%. And that return is, if anything, even more guaranteed than the CD's!

Second, for most people, getting that mortgage paid off before you retire makes an awful lot of sense.

The benefits of a mortgage-free retirement
There are lots of reasons to dump the home loan before you dump your work life. First and foremost, owning your home free and clear when you retire will lower your monthly costs significantly. That'll extend the life of your retirement savings and give you more freedom to do all that fun I'm-retired stuff, like traveling, taking classes, or annoying your offspring by sending extravagant gifts to your grandchildren.

Beyond that, there are the obvious peace-of-mind benefits that come with owning your home outright. And having that home equity when you retire gives you some wiggle room to take a home equity loan or even a reverse mortgage, should you need it.

But ...
While all of this seems like common sense, there are (quite sensible) folks who will argue the opposite side of the coin: If you're only paying 5% on that mortgage, doesn't it make sense to invest the money in the stock market, instead of paying it off?

The 5% you'd get from paying off your mortgage is a risk-free return, and as we've all learned in recent years, no stock is risk-free. But we can still find some relatively safe bets. Consider National Grid (NYSE: NGG), a U.K.-based utility company that owns and operates energy transmission networks in the U.K. and the eastern U.S. Because it owns the networks, the company is able to generate a massive, stable cash flow, some of which it passes on to shareholders via a fat 7.5% dividend yield.

Or how about France Telecom (NYSE: FTE), the Ma Bell of France, which has parlayed (get it?) its long-standing landline business into about a 50% share of France's wireless market, with big presences in Great Britain, Poland, and Spain as well. It isn't the only telecom with a fat dividend yield (5.4%), but with some room for capital appreciation, it'll still beat your mortgage more often than not. While we're in France, there's also oil giant Total (NYSE: TOT), with a 5% dividend yield and a share price that will benefit should oil prices continue to rise over time.

I'm sure you could find plenty of others. The point is, yes, you can outperform the benefits of paying off your mortgage if you're willing to assume some risk. But as risk-free investments go, the mortgage is hard to beat.

Make it part of your plan
Here's the takeaway: If your retirement is more than a few years away, it probably makes sense for you to think seriously about including your mortgage in your overall retirement savings plan, if you haven't done so already.

Now, I said "probably" because it turns out that there are a few more situations in which keeping the mortgage around for awhile actually makes sense. Foolish retirement guru Robert Brokamp, who has an article looking at all of this in the new issue of the Fool's Rule Your Retirement newsletter, agrees that paying off the house before you leave work makes sense for most. But he also argues that it doesn't make sense in a few specific circumstances, at least one of which seems likely to be a possibility for many Fools.

I don't have the room to summarize it all here, but if you've read this far, I urge you to check out Robert's article for the full lowdown. Rule Your Retirement is a paid service, but you can get full access for 30 days with a free trial. Just click here to get started.

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Fool contributor John Rosevear doesn't have a position in the companies mentioned. France Telecom, National Grid, and Total are Motley Fool Income Investor recommendations. You can try Income Investor or any of our other Foolish newsletter services free for 30 days.

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