Some tips for consumers about switching carriers:

. The Federal Communications Commission advises consumers not to terminate their service before contacting the carrier to which they want to switch. Those who cancel service before making the switch will lose their phone numbers.

. When contacting the new carrier, consumers should have their phone number, billing address, account number and latest bill. Only the person whose name is on the account can authorize the change.

. Consumers should expect a transfer from a landline company to take about four days. For wireless-to-wireless transfers, the FCC says the goal is to transfer a single number within 21/2 hours after the new carrier calls the old provider.

. Consumers should be aware that carriers can charge their customers for switching the number, though a new carrier could agree to pay the transfer fee the way long distance companies often pay the cost of changing service as a way to entice customers.

. Consumers who have contracts with their current cell providers will have to pay early termination fees, which can reach $200, if they switch before their agreements expire.

. While wireless customers can keep their numbers, they may not get to keep their phones. Most will have to buy a new cell phone when changing providers because each company uses different technology.