Anyone making a phone call in Alberta will now have to add the area code first, as 10-digit dialing began in the province on Monday.

For the next two months, anyone who doesn't dial the area code will hear a reminder message, but the call will still go through.

Telus says it has to make the change because the growing province is running out of phone numbers. Two new area codes — 587 and 825 — are also being added to accommodate new numbers.

"There's a technological aspect to it as well," explained Chris Gerritsen, speaking for Telus. "People don't necessarily just have their one phone number anymore. They've got various devices. They've got a cellphone, BlackBerry, perhaps they have a wireless aircard for their laptop and all these devices require their own telephone numbers."

The reminder message will be turned on through the week, said Jim Johannson, director of media relations at Telus.

"So if you don't hear the announcement today, you for sure will within the next couple of days," he said.

The transition period ends on Sept. 12, when calls will only go through when all 10 digits are dialed.

Switch is a boon to some businesses

A sign has already been erected outside a southwest Calgary store that reads "Are you ready for 10-digit dialing?"

"There are many companies who have vehicle lettering, storefront signage, that kind of thing, with their phone numbers on it, and all those phone numbers need to be updated," said Bill Webster, owner of Speedpro Signs.

Companies that service telephone systems have also been busy working to reconfigure long distance restrictions, speed dialing and voice mail setups.

"Our phone's been ringing off the hook this morning, but we were proactive, and we compiled a list of all the customers we had," said Perry Allen, president of Calgary Telephone and Wiring.

"It's not really critical right now, but we want to make sure we get everyone covered off before the September deadline."

People in the Toronto, Montreal and Vancouver areas have already been punching in 10 numbers to make calls for several years.