Cosham railway station serves Cosham, a northern suburb of the city of Portsmouth, Hampshire in southern England. It is 90 miles 6 chains (90.08 miles, 144.96 km) from London Waterloo.

Opened in 1848 by the London and South Western Railway (LSWR), it is located on the West Coastway Line which runs between Brighton and Southampton. It is currently served by the South Western Railway, Southern, and Great Western Railway train operating companies.

The station used to have a small goods yard which served local freight trains around Portsmouth. Today all that remains is an old loading gauge, with the original site being built upon.

Services at Cosham are operated by Southern, South Western Railway and Great Western Railway using Class 377, 444 and 450 EMUs and Class 158, Class 165 and 166 DMUs.

Great Western Railway services between Cardiff and Portsmouth pass through without stopping after 8pm.

The typical off-peak service in trains per hour is:

• 1 tph to London Waterloo via Basingstoke
• 2 tph to Brighton via Worthing
• 3 tph to Southampton Central
• 1 tph to Cardiff Central via Bristol Temple Meads
• 3 tph to Portsmouth & Southsea of which 2 continue to Portsmouth Harbour

The station is also served by a single daily service from London Waterloo to Southampton Central via Guildford, which runs directly to Cosham from Bedhampton.

Westward, the line through Cosham leads to Portchester and Fareham, eastward to a junction (part of the local "Railway Triangle") between lines leading south to Hilsea and Portsmouth and east to Bedhampton and Havant.

Preceding station	National Rail			Following station
Portchester or Fareham		Southern West Coastway Line		Havant
Portchester		South Western Railway West Coastway Line		Hilsea
		South Western Railway Portsmouth Direct Line Limited Service		Bedhampton
Portchester or Fareham		Great Western Railway West Coastway Line Not Evenings		Fratton

• 
  The crossing gates descend
• 
  An up train departing
• 
  Looking east from the High Street footbridge
• 
  Cosham Station in August 1969.

• 
  The view from the Knowlsey Road footbridge
• 
  Looking from the down towards the up platform
• 
  SR Merchant Navy Class 35028 Clan Line passing through Cosham Station
• 
  A 1910 Railway Clearing House map of lines around Cosham railway station

• Train times and station information for Cosham railway station from National Rail

50°50′31″N 1°04′03″W / 50.84194°N 1.06750°W / 50.84194; -1.06750