Verizon

If you're considering signing up for wireless service with Verizon, you may want to do so before Sunday.

That's when the New York-based telecommunications giant adds a $20 fee to cover the cost of activating a new device, according to a company spokeswoman. It applies to consumers signing up for a new phone or tablet line and affects devices purchased through a monthly installment plan or purchased outright.

The activation fee makes its return a few months after Verizon killed off its smartphone subsidies and service contracts, forcing new customers to into installment plans. The device activation fee had been waived.

The fee come at a time when carriers are curiously raising the price of their services despite intensifying competition. T-Mobile just raised the price of its service for new customers, and Sprint in October hiked the rate of its unlimited data plan.

The fee was first reported by Droid Life earlier this week.

The $20 fee is half the amount of the activation fee for its now defunct two-year contract. AT&T charges a $15 fee for devices sold through its installment program, or $45 for a two-year contract or purchased device.

Verizon is also slated to raise the monthly rate of its unlimited data plan by $20 a month on Sunday. It is the first day that customers with these grandfathered plans, the company stopped offering unlimited data plans to new customers in 2011, will be able to take part in Verizon's device installment plan.