There are several companies that are interested in having the fastest internet connection possible for a low cost.  They might consequently be interested in a T3 and DSL are both service access technologies. A T3 is usually a business product, while DSL can service both business and residential customers.

When it comes down to it, T3 is the best choice if immediate responses and reliability are critical to the applications you use on your connection or if you host an in-house email or web servers.

If not, DSL may be a great option for you. DSL can run as fast as T3 but speeds are variable depending on load and design factors. T3s are generally more reliable and have a shorter time to repair.

One way to see if you need T3 service is to evaluate your current usage and telecom expenses. If you meet any of the following criteria, a T3 line may be the best option for your business. A T3 line is a digital transmission link with a capacity of 1.544 Mbps. T3 lines are used to access voice and data, including the public telephone network and the Internet, and to create private networks. A variety of services can be accessed with a T3 line.
Also, you can have a dedicated T3 line for voice services, broadband Internet access, integrated broadband and long distance service.  Dedicated Voice Services consist of local, long distance like interstate, intrastate and international and toll free services. The cost of these services varies depending on where you are calling and your carrier. Dedicated Broadband Internet Access provides 1.544 Mbps capacity for both uploading and downloading from the Internet.

Keep in mind that most costs in a metro area are around $500, with one-time charges ranging from $500-1,000 contingent upon the work required and equipment needed.  The cost for integrated service varies with capacity, features and services.

This is a great option for typical companies with five to twenty employees. One of the main differences between a T3 line and DSL is the cost. While DSL is not as fast or reliable as a T3 circuit, it is substantially less expensive.

The cost of DSL services has gone down due to deregulation, competition and the decreasing costs of equipment and supplying bandwidth, while T3 lines remain in the higher price range because of the robust technology they utilize.

Usually, DSL costs around $120/month for low-end service and up to $500/month for faster service. A T3 line can cost between $1,000-1,500/month depending on who provides it and the customer's location.