The river rises from Clark Pond in "Foster, Rhode Island. From there, it flows south through "Foster and "Coventry, then turns west and heads into Connecticut, flowing through "Sterling and "Plainfield to its mouth at the "Quinebaug River.
The American Rivers organization has targeted the Moosup River for dam removal to help fish to swim upstream to spawn. In late June 2014 Moosup Dam #1 in Connecticut was removed  and on September 29, 2015 the Griswold Rubber dam in Connecticut was removed.
Below is a list all crossings over the Moosup River. The list starts at the headwaters and goes downstream.
|Moosup Valley Road|
|"Kent||"Coventry||Barbs Hill Road|
|"" "RI 14|
|"" "CT 14A|
|"" "CT 14|
|"Plainfield||"" "CT 14|
|Barber Hill Road|
|South Main Street|
|"" "CT 12|
|Black Hill Road|
In addition to many unnamed tributaries, the following brooks feed the Moosup:
|This article related to a river in Connecticut is a "stub. You can help Wikipedia by expanding it.|
|This article related to a river in Rhode Island is a "stub. You can help Wikipedia by expanding it.|