At a time when wireless download speeds are becoming faster, Comcast is raising its residential Internet speeds for free in an effort to remain ahead of its competitors.

Beginning Tuesday, Comcast is increasing the speed of its most popular residential Internet service offerings. The company's 15-megabit download speed (currently $64.95 a month) will increase to 25 megabits for the same price. The 25-megabit speed (currently $74.95) will increase to 50 megabits at the same price. And the 50-megabit speed (currently $114.95) will increase to 105 megabits at the same price. Prices are $15 a month less if Internet service is bundled with TV or telephone service. Upload speeds also are increasing, but, as before, they remain far slower than download speeds.

Comcast also offers slower tiers of residential Internet service with download speeds of 1.5 megabits, 3 megabits and 6 megabits, and those speeds will remain unchanged. Comcast's business Internet service also won't be affected by the changes.

Comcast says it is making the changes to accommodate customers who want to stream or download Internet video, and for those who have an increasing number of Internet­-connected devices in their homes that all compete for part of the available Comcast download speed.

The 50-megabit tier of service, in particular, had not attracted as many customers as hoped and is being raised to 105 megabits to make it more attractive, said David Tashjian, Comcast's vice president of sales and marketing.

Wireless competition

The cable giant is speeding up its Internet service at a time when 4G wireless services have become viable competitors for fast Internet speeds, offering download speeds of 9 megabits or more, and providing mobility that Comcast's fiber optic network can't offer. And, like Comcast, 4G services are available at their highest speeds in most of the metro area, whereas the speed of telephone-based Internet services varies widely based on the capacity of local phone cables.

While Comcast does not limit the amount of data a consumer can download per month, something most wireless companies do limit, it is conducting tests to determine what those limits should be set at nationally, Tashjian said.

Comcast is rolling the faster Internet service out by individual cable TV markets, and offered the service earlier this year on parts of the East and West Coasts and in Chicago. It plans to upgrade most of its cable TV properties by the end of this year.

The Comcast network can handle the faster Internet speeds, although some equipment upgrades at Comcast and in the homes of some consumers will be needed. Some, but not all, consumers may need a new cable modem to utilize the faster speeds available, and as a result the company will exchange their existing modems for new ones at the same rental cost ($7 a month) if necessary, Tashjian said. Comcast will be in touch with customers to explain what, if anything, they need to do with their cable modems, he said. Customers can also buy their own modems, as before.

Steve Alexander • 612-673-4553