11 January:Brighton & Hove, South Portslade (2027). Les Hamilton (Labour) has resigned.
Dorset, Littlemoor & Preston (2024). Tony Ferrari (Conservative) has died.
Salford, Quays (2026). Alex Warren (Liberal Democrat) has resigned.
Tendring, Bluehouse (2027). Ian Lennard (Labour) has resigned.
18 January:Hackney, Cazenove (2026). Caroline Woodley (Labour) has been elected mayor.
Richmond upon Thames, Hampton North (2026). Geoffrey Samuel (Conservative) has died.
Richmond upon Thames, Teddington (2026). Martin Elengorn (Liberal Democrat) has died.
Sheffield, Stannington (2026). Vickie Priestly (Liberal Democrat) has died.
Wandsworth, Tooting Broadway (2026). Kate Forbes (Labour) has resigned.
Warwick, Warwick All Saints & Woodloes (2026). Raj Kang (Labour) has resigned.
25 January:Stirling, Dunblane & Bridge of Allan (2027). Douglas Dodds (Conservative) has resigned.
8 February:
Blaenau Gwent, Ebbw Vale South (2027). Carl Bainton (Labour, elected as Independent) has ceased to be a councillor.
Cheshire East, Crewe Central (2027). Anthony Critchley (Labour) has resigned.
Gwynedd, Criccieth (2027). Eirwyn Williams (Independent) has died.
West Northamptonshire, East Hunsbury & Shelfleys (2025). Suresh Patel (Conservative) has resigned.
22 February:Scottish Borders, Jedburgh & District (2027). Pam Brown (SNP) has resigned.
Known Vacancies where a byelection is expected:Buckinghamshire, Farnham Common & Burnham Beeches (2025). David Anthony (Conservative) has ceased to be a councillor.
Buckinghamshire, Hazlemere (2025). Ron Gaffney (Conservative) has died.
Cambridgeshire, Yaxley & Farcet (2025). Mac Maguire (Conservative) has died.
Dacorum, Tring West & Rural (2027). One of the two Lib Dem councillors has ceased to be a councillor.
Derbyshire Dales, Norbury (2027). Tony Morley (Conservative) has died.
East Hampshire, Four Marks & Medstead (2027). Joanna Nelson (Liberal Democrat) has ceased to be a councillor.
East Riding of Yorkshire, Minster & Woodmansey (2027). Peter Astell (Liberal Democrat) has died.
East Riding of Yorkshire, Tranby (2027). Viv Padden (Liberal Democrat) has died.
Folkestone & Hythe, Romney Marsh (2027). Liz Grant (Conservative) has ceased to be a councillor.
Glasgow, Hillhead (2027). Hanzala Malik (Labour) has died.
Horsham, Henfield (2027). Malcolm Eastwood (Independent) has ceased to be a councillor.
Ipswich, St John's (2026). Sophie Connelly (Labour) has died.
Lancaster, Carnforth & Millhead (2027). Paul Gardner (Labour) has died.
Neath Port Talbot, Briton Ferry East (2027). Chris James (Independent) has ceased to be a councillor.
Neath Port Talbot, Neath East (2027). Sheila Penry (Labour) has died.
Neath Port Talbot, Rhos (2027). Marcia Spooner (Plaid Cymru) has died.
North Tyneside, Cullercoats (2024). Linda Arkley (Conservative) has died.
Wiltshire, Calne Chilvester & Abberd (2025). Tony Trotman (Conservative) has died.
Worcestershire, Evesham North West (2025). Peter Griffiths (Conservative) has died.
Known Vacancies where the six month rule applies and so a byelection will not be held:Barnsley, Darton East (2024). Mat Crisp (Liberal Democrat) has resigned.
Barnsley, Kingstone (2024). Pooja Ramchandani (Labour) has ceased to be a councillor.
Basildon, Billericay East (2027). David Dadds (Conservative) has ceased to be a councillor.
Castle Point, Canvey Island North (2024). John Payne (Canvey Island Independent Party) has ceased to be a councillor.
Havant, Hart Plain (2024). Carly Scannell (Conservative) has ceased to be a councillor.
Newcastle-upon-Tyne, Lemington (2024). Jason Smith (Newcastle Independents) has resigned.
Pendle, Earby & Coates (2024). Rosemary Carroll (Conservative) has ceased to be a councillor.
Rossendale, Longholme (2024). Steve Hughes (Labour) has resigned.
Stroud, Nailsworth (2024). Norman Kay (Green) has died.