Tributaries of the River Thames

This article lists the tributaries of the River Thames from the sea to the source, in England. There are also secondary lists of backwaters of the river itself and the waterways branching off.

Note: the River Medway shares the saline lower Thames Estuary.

Tributaries
The average discharge is taken from the lowest point at which measurements are taken, which may be upstream of the confluence.

Backwaters and cuts
This list comprises the principal instances; longest ex-mill races (leats), with own articles are included; the main weirstream/river stream of each Thames lock is omitted and the smallest such associated instances but the Sheepwash Channel is included for its importance in Oxford.