Iowa, Minnesota and South Dakota Calling Restriction

We would like to first thank you for using our services. With regards to call termination issues to Iowa and Minnesota as you have reported, we apologize for the inconvenience as this problem relates to call restrictions to these destinations. Unfortunately, the situation that led to the restrictions is beyond our control as enormous rates leave us with the unfortunate position that we are hereby advising of.

This restriction is imposed due to rate hikes of approximately 1841% to several NPA-NXXs in Iowa and Minnesota. The percentage is not exaggerated. This rate hike is due to the Independent Phone Companies that operate these NPA-NXXs teaming up with companies offering free calling services. This is causing a drastic increase in the volume of calls Local Exchange Carriers (LECs) terminated to these areas.

The Independent Phone Companies’ settlement rates billed to the LECs is very costly, much higher than standard Bill and Keep rates charged between two LECs. Several LECs in the US have filed complaints with the US regulators (FCC) to have this practice stopped, because their costs are absolutely crippling. Here’s a link to one of the news articles if you’re interested that outlines the problem descriptively.


As a result, an executive decision was made by the governing bodies of Distributel (parent company to ThinkTel) to limit/restrict traffic to NPA-NXXs for the rate centers below. This unfortunately means that at times you will not be able to complete calls to the destinations.

What you will experience when calling during the even hours, i.e. 00:00 to 00:59, 02:00 to 02:59, and 22:00 to 22:99, is that calls will be restricted to only allow a small number of calls to these NPA-NXXs through at a time. Additional calls will be terminated with a fast busy or treatment stating that “the number you have dialed cannot be reached from this line”.

During the odd hours, i.e. 01:00 to 01:59, 03:00 to 03:59, and 23:00 to 23:59, all calls to theses NPA-NXXs will be terminated with a fast busy treatment or treatment stating that “the number you have dialed cannot be reached from this line”.

Calls will not be suddenly terminated if the time changes from an even hour to an odd hour; the call will stay up until someone hangs up.


The affected NPA-NXXs are:

Iowa Nebraska Minnesota Montana North Dakota South Dakota Wisconsin
319-279 308-344 218-283 406-208 701-776 605-214 715-463
563-224 308-384 218-339 406-256 701-925 605-360 715-488
641-527   218-385 406-265   605-454 715-689
641-594   218-463 406-273   605-473  
641-715   218-486 406-323   605-475  
712-338   218-548 406-335   605-477  
712-421   218-632 406-338   605-562  
712-429   218-681 406-450   605-692  
712-432   218-790 406-590   605-715  
712-451   218-855 406-679   605-725  
712-580   218-862 406-696   605-868  
712-775   218-895 406-750      
712-853   218-936 406-765      

We apologize for any inconvenience that this issue presents to you or your customers. Unfortunately, there’s nothing that we’re able to do to change the reality of the situation.

Please contact your account representative if you have additional questions or concerns regarding this matter.