En español | We've all heard the old saying, "Nothing is certain but death and taxes." Although when you stop to think about it, I suppose most of us would add "monthly bills" to that list.

See also: 10 financial tools you should use.

So-called fixed expenses — those items in our household budgets that we consider unavoidable and non-negotiable — typically account for a big chunk of what we spend every month. According to the U.S. Department of Labor's annual Consumer Expenditure Survey, about two-thirds of the average American family's household spending is for basic necessities, as opposed to discretionary expenses. Between rent or mortgage payments, insurance, utilities, phone bills, car payments and more, most folks can relate to the lyrics of that popular country song: There's just too much month at the end of the money.

Fix your fixed expenses. — Photo by Uppercut/Getty Images

But maybe at least some of our fixed expenses aren't as fixed as we think they are. Think of the money you could save if you could knock down — or even eliminate — some of your routine bills. Consider:

Bundling: Consolidating insurance policies or telecommunication services with a single company can often  lower what you pay. For example, "bundling"  your automobile, homeowner's and other insurance policies with one insurance company will typically allow you to qualify for discounts and special pricing that could save you 10 percent or more in total premiums. It's worth looking into, although it can be tricky and sometimes even end up costing you more.

Switching vendors: When the economy is in a slump the upside is that  customers are kings. I like to set aside a day or two every year to review my fixed expenses and do a little comparison shopping. Using the Internet and resources like Consumer Reports, it's easy to get a feel for whether you can do better by switching vendors, canceling your gym membership or even refinancing your home. In this economy, it pays to constantly shop around. Don't make your final decision about whether to switch or stay put simply on the basis of your online and other research. Before you actually jump ship, talk to all the players involved, including your current vendor(s). Often times when vendors know that your business is up for grabs, they'll sweeten the pot even more.

Asking for a better deal: It never hurts to ask a company service whether they can charge you less. Be polite and direct when you ask for a better deal. There's nothing wrong with calling up a vendor and explaining that times are tough and you're looking for ways to trim your expenses. There might be discounts or special promotions you're eligible for, and other times it might be possible to make adjustments in the type of plan you have, resulting in lower payments. 

Seeking public assistance: If you're having trouble paying for even the most basic living expenses, you may qualify for financial assistance through a variety of government and nonprofit institutions. To research government-sponsored assistance programs at both the federal and state levels, start by visiting the official benefits website of the U.S. government; it includes links to assistance programs offered by all 50 states. National nonprofit organizations including the Salvation Army and the American Red Cross offer various programs through their local chapters to provide help in paying for utilities and other household expenses, and local offices of the United Way are a good source of information about other charitable organizations in your community that offer financial assistance programs to people in need.

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