Even though the state's electricity markets were deregulated more than a decade ago, many residents still struggle to understand the hundreds of plans available for purchase.

Yet picking the right one is crucial because, in some cases, a family's electric bill can be its greatest monthly expense aside from housing. Finding a plan that's just a few pennies cheaper per kilowatt-hour can result in hundreds of dollars in annual savings.

Here are the answers to some common questions about selecting an energy provider.

Q: Where should I start?

A: The best place to look for an electricity plan is PowertoChoose.com, the state-sanctioned website that acts as a clearinghouse for residential electricity plans. Customers can plug in personal details and sort plans by price to find the offer that's best for them. The site also allows users to look at electric providers' customer service records. Consumers should be aware that while there are websites with similar names, Power to Choose is the only one affiliated with the Public Utility Commission, Texas' electricity regulator. If you don't have Internet access, call 866-797-4839 for help selecting a plan.

There's often more to a plan than the average price displayed on the Power to Choose website. So the best way to choose is to narrow your options to four or five plans that could be a good fit, then start looking through the fine print to decide which is best. The details contained in a pair of documents known as the Electricity Facts Label and the Terms of Service can often mask the real costs of a plan.

"A lot of companies end up competing on confusion instead of price," said Jake Dyer, a policy analyst with the Texas Coalition for Affordable Power, a consortium of Texas cities that advocates for electricity customers.

Q: When can I change plans?

A: Most fixed-rate plans charge customers an early termination fee if they switch providers before their contract expires. You can find out when your contract ends by contacting your electric provider or checking your account details online. You're also supposed to receive a letter in the mail at least 30 days before your contract expires.

When you change providers, you'll be able to indicate the date you want the switch to occur. Customers can switch providers without facing an early termination fee if they schedule the switch no earlier than 14 days before their current plan expires, according to the Public Utility Commission.

Most variable-rate plans are month to month and don't charge early termination fees, so customers on those plans can switch at any time. Check your plan for details.

If you did nothing when your last plan expired, you're on a plan your provider picked for you - and chances are you're not getting the best deal available.

Q: Should I pick a fixed-rate or variable-rate plan?

A: Fixed-rate plans come with a contract for a predetermined period, from a few months to a few years. For the length of the plan, customers are locked into a rate that won't change. Essentially, the only factor that should affect their monthly bill is the amount of electricity they consume.

With a variable-rate plan, your cost of electricity can change every month. Looking at the rates displayed on the Power to Choose website doesn't always help you determine what you'll pay in the future. Some variable-rate plans also have especially tempting introductory rates that can change after just a month.

Customers considering variable-rate plans should look at the Electricity Facts Label to get a link to a website showing historical rates associated with a plan, said Carol Biedrzycki, executive director of Texas ROSE, which advocates on behalf of low-income Texans on electricity issues.

The potential upside of a variable rate plan is that customers can theoretically wind up with lower rates depending on market conditions. But they can also get sticker shock if they don't monitor their rates regularly.

"You're just not sure what you're going to end up with," Dyer said.

"For most people, I think some level of certainty may help them avoid some indigestion down the road."

Q: Does it matter whether your provider has a recognizable name?

A: Some customers are under the mistaken belief that if they choose a provider with a familiar name, their service will be more reliable, and they'll get their power restored more quickly in the event of an outage. That's not true.

In the Houston area, all electricity - regardless of provider - is delivered through CenterPoint power lines. When there's an outage, CenterPoint is tasked with restoring it, not the retail provider.

More important than your provider's name is its customer service record. On Power to Choose, customers can see how many complaints people have made to the state about a particular company. Some well-known companies have poor scores. Some companies with names you've never heard of score well.

Q: What about prepaid plans?

A: Consumer advocates say prepaid plans target customers who don't have good credit. Prepaid plans tend to have higher rates per kilowatt-hour, and many prepaid plans come with an assortment of fees. Prepaid plans also operate under different consumer protection rules than typical plans, and that can result in customers receiving much less notice before they're cut off for nonpayment.

"Prepaid plans are not a good option," Biedrzycki said.

Q: What are minimum usage fees?

A: Some electric plans charge fees for customers who don't use a certain amount of electricity. Others offer discounts to customers whose usage exceeds a certain level. The net effect is the same: Customers with energy usage below a certain threshold - often 800 to 1,000 kilowatt-hours per month - can wind up paying for electricity they didn't use. You can see if the plan you're considering has a minimum usage fee in its Electricity Facts Label or Terms of Service.

Minimum usage fees can nullify savings customers might expect when they conserve power. Customers in smaller homes, including apartments, should pay particular attention to these fees. Check your old bills to see how much power you consume throughout the year to get a sense of how often you'll likely have to pay the fee.

"It was kind of disturbing when this started to become a trend," said David Power, deputy director of the watchdog group Public Citizen. "It's almost ubiquitous."

Q: What other fees should I watch out for?

A: There's almost no limit to the types of fees electricity providers try to levy on their customers. Some companies charge you anytime you make a payment. A few assess fees for speaking to customer service agents by phone. Some charge for a paper copy of the bill. Some companies even charge customers for their own credit check.

To avoid signing up for a plan with unreasonable fees, be sure to read the Electricity Facts Label and the Terms of Service. It's a lot to take in, but failure to do so could cost a lot in the long run. Biedrzycki said if it seems overwhelming, just keep an eye out for numbers - and read what's around them.

"That's where the hidden fees come in," Biedrzycki said.

Q: Are the freebies worth it?

A: It's become popular for electric providers to offer freebies like high-tech thermostats, restaurant gift cards or sports team apparel for customers who enroll in particular plans. Generally speaking, watchdogs say, it's not a good idea to pick a plan based on giveaway items.

"It's pretty gimmicky," Dyer said. "Keep in mind, your electricity bill may be the single biggest bill you have outside of rent or a car payment. When you pay $1,000 or more over the course of a year, you have to ask: Is it really worth it?"

The same goes for plans that offer free nights and weekends. Those plans may have significantly higher rates the rest of the week. They may make sense for someone who owns a vacation home, but not for too many other people, Dyer said.

Q: Can you negotiate?

A: Absolutely. Power to Choose lists only some of the available plans, typically those designed to lure new customers. But Power, of Public Citizen, said some electricity providers may be willing to go even lower on price to get a new customer or avoid losing an existing one.

"I'd be aggressive. Nobody wants to advertise what they'll really sell it for, but they're required to put something" on Power to Choose, he said.