There are currently 99 known vacancies, excluding 2 arising from the recent death of a Councillor, at least 89 of which will be contested on 4 May 2017. Those already known to have been called are marked with *.
This can be compared with 114 by-elections in England on 2 May 2013, a similar point in the last election cycle, when Conservatives defended 64 seats, Labour 27, Liberal Democrats 20 and Greens 3.
Conservative held seats - 55
- vacancy following a death* Central Bedfordshire UA, Shefford
* Havant BC, Emsworth
* Melton BC, Melton Sysonby
North Hertfordshire DC, Royston Heath
* Preston BC, Preston Rural East
* Slough UA, Haymill & Lynch Hill
South Derbyshire DC, Woodville
* South Somerset DC, Blackmoor Vale
* West Devon BC, Bere Ferris
- vacancy following a resignation
* Aylesbury Vale DC, Wendover & Halton
* Breckland DC, Harling & Heathfield
* Bradford MB, Queensbury
* Central Bedfordshire UA, Biggleswade North
* Charnwood BC, Birstall Wanlip
* Chichester DC, Bosham
* Chichester DC, East Wittering
* Chichester DC, North Mundham
* Chichester DC, Plaistow
* Craven DC, Aire Valley & Lothersdale
* Dacorum BC, Berkhamsted West
* Daventry DC, Long Buckby
* East Devon DC, Broadclyst
* East Devon DC, Whimple
* East Hertfordshire DC, Datchworth & Aston
* East Northamptonshire DC, Prebendal
* Fylde BC, Warton & Westby
* Hertsmere BC, Potters Bar Oakmere
* Huntingdonshire DC, St Neots Eaton Ford
* Ipswich BC, Stoke Park
* Kettering BC, Burton Latimer
* Kettering BC, St Peters
* Maidstone DC, Bearsted
* Mendip DC, Frome College
* Mid Sussex DC, Bolney
* Mid Sussex DC, Burgess Hill Franklands
North Hertfordshire DC, Hitchen Priory
* Reigate & Banstead DC, Tadworth & Walton
* Rugby BC, Coton & Boughton
* Runnymede DC, Foxhills
* Rushcliffe BC, Thoroton
* South Cambridgeshire DC, Bourn
* South Northamptonshire DC, Kings Sutton
* South Staffordshire DC, Penkridge West
* Spelthorne BC, Ashford East
* Stratford-on-Avon, Ettington
* Teignbridge DC, Kingsteinton East
* Teignbridge DC, Newton Abbot Bushell
* Welwyn Hatfield BC, Panshanger
* West Oxfordshire DC, The Bartons
West Somerset DC, Minehead North
* Windsor & Maidenhead UA, Clewer North
* Worcester BC, Bedwardine
* Wychavon DC, Droitwich South East
* Wychavon DC, Evesham South
* Wyre Forest DC, Mitton
Labour held seats - 29
- vacancy following a death
* Blackburn with Darwen UA, Marsh House
* Exeter BC, St Thomas
Kings Lynn & West Norfolk BC, Fairstead
* Oxford BC, Barton & Sandhills
* Stevenage BC, Roebuck
* Wirral MB, Claughton
- vacancy following a resignation
* Birmingham MB, Hall Green
Blackburn with Darwen, Higher Croft - voided
* Cambridge BC, Arley
* Camden LB, Gospel Oak
* Carlisle BC, Belle Vue
* Carlisle BC, Yewdale
* Dover DC, Buckland
* East Staffordshire DC, Horninglow
* East Staffordshire DC, Shobhall
* Hartlepool UA, Headland & Harbour
* Liverpool MB, Wavertree
* Manchester MB, Rusholme
Nottingham UA, Sherwood
* Nuneaton & Bedworth BC, Bulkington
* Preston BC, Ashton
* Rugby BC, New Bilton
* Sedgemoor DC, Bridgwater Eastover
Sheffield MB, Southey
* Stafford BC, Highfields & Western Downs (2 vacancies)
* Trafford MB, Broadheath
* Watford BC, Leggatts
York UA, Micklegate
Liberal Democrat held seats - 7-
vacancy following a death
* Birmingham MB. Perry Bar
-
vacancy following a resignation* Cheltenham BC, All Saints
* Eastleigh BC, Eastleigh Central
* South Lakeland DC, Ambleside & Grasmere
* Test Valley DC, Valley Park
* Watford BC, Oxhey
* Watford BC, Park
Independent held seats - 4
- vacancy following a deathRichmondshire DC, Reeth & Arkengarthdale
- vacancy following a resignation
* Chiltern DC, Great Missenden
* Melton BC, Egerton
* Mid Suffolk DC, Eye
Residents held seats - 1- vacancy following a resignation
* Uttlesford DC, Newport
Green held seats - 1
- vacancy following a resignation
* Malvern Hills DC, Malvern West
UKIP held seats - 2
- vacancy following a resignation
* Dover DC, Maxton, Elms Vale & Priory
* Lichfield DC, Fazeley