The two main considerations when choosing a toll free calling program are the rates you will pay and the features you require.

Rates range from nearly 30 cents per minute on some plans to less than 10 cents per minute with some high-volume programs. As a result, the plan you choose can have a tremendous effect on how much you end up paying for the service.

Most plans offer a similar set of basic calling features, although monthly charges and set-up charges may differ. You may want to look for options such as call blocking, which ensures that you do not get (and pay for) calls from areas you do not serve, or account codes, which restrict inbound access to employees or customers who know the correct code.

Larger businesses with dedicated inbound service can also consider more sophisticated features. If a business has more than one toll free number, Dialed Number Identification Service (DNIS) identifies the particular toll free number that was dialed. This can be used to distinguish between different marketing campaigns that all ring at a central location.

Another identification feature, known as ANI, is the same as caller ID service for the home. ANI allows a business to see the caller's number as the call is received. Some firms use this information to bring up customer information on a computer as the call comes through.