County ins and outs:
Derbyshire
Ins: Tom Lace (Season long loan from Middlesex), Logan van Beek (Overseas), Kane Richardson (Overseas - Vitality Blast), Billy Stanlake (Overseas - Vitality Blast)
Outs: Ben Slater (Nottinghamshire), Will Davis (Leicestershire), Gary Wilson (Released), Gareth Brodrick (Released), Hardus Viljoen (released)
Durham
Ins: Alex Lees (Yorkshire), Ben Raine (Leicestershire), Cameron Bancroft (Overseas), D'Arcy Short (Overseas - Vitality Blast)
Outs: Paul Collingwood (Retired), Barry McCarthy (Retired)
Essex
Ins: Jack Plom, Cameron Delport (Leicestershire), Mohammad Amir (Overseas - Vitality Blast), Adam Zampa (Overseas - Vitality Blast)
Outs: James Foster (Retired), Ashar Zaidi (Released), Callum Taylor (Released), Matt Dixon (Released)
Glamorgan
Ins: Billy Root (Nottinghamshire), Charlie Hemphrey (Queensland Bulls), Marnus Labuschagne (Overseas)
Outs: Aneurin Donald (Hampshire)
Gloucestershire
Ins: Stuart Whittingham, Michael Klinger (Overseas - Vitality Blast)
Outs: Liam Norwell (Warwickshire), Craig Miles (Warwickshire), Kiaran Noema-Barnett (Released)
Hampshire
Ins: Keith Barker (Warwickshire), Aneurin Donald (Glamorgan), James Fuller (Middlesex), Harry Came, Aiden Markram (Overseas) Ajinkya Rahane (Overseas)
Outs: Jimmy Adams (Retired), Sean Ervine (Retired), Asher Hart (Released), Reece Topley (Released), Calvin Dickinson (Released), Chris Sole (Released)
Kent
Ins: Matt Milnes (Nottinghamshire), Fred Klaassen (Netherlands), Jordan Cox, Matt Renshaw (Overseas), Mohammad Nabi (Overseas - Vitality Blast), Adam Milne (Vitality Blast)
Outs: Will Gidman (Retired), James Tredwell (Retired), Mat Hunn (Retired)
Lancashire
Ins: Richard Gleeson (Northamptonshire), George Lavelle, George Balderson, Glenn Maxwell (Overseas), Joe Burns (Overseas)
Outs: Jordan Clarke (Surrey), Simon Kerrigan (Released), Karl Brown (Released), Arron Lilley (Leicestershire)
Leicestershire
Ins: Chris Wright (Warwickshire), Will Davis (Derbyshire), Arron Lilley (Lancashire)
Outs: Michael Carberry (Released), Cameron Delport (Released), Ned Eckersley Released), Mark Pettini (Released), Rob Sayer (Released), Tom Wells (Released), Richard Jones (Released), Zak Chappell (Nottinghamshire), Ben Raine (Durham)
Middlesex
Ins: Jack Davis, Mujeeb ur Rahman (Overseas - Vitality Blast), AB De Villiers (Overseas - Vitality Blast), Ross Taylor (Overseas - Royal London One Day Cup)
Outs: Nick Compton (Retired), Tom Lace (Derbyshire on a season long loan), Ravi Patel (Released), James Fuller (Hampshire),
Northamptonshire
Ins: Blessing Muzarabani, Jason Holder (Overseas), Faheem Ashraf (Overseas)
Outs: Ben Duckett (Nottinghamshire), Richard Gleeson (Lancashire), Steven Crook (Retired)
Nottinghamshire
Ins: Ben Duckett (Northamptonshire), Ben Slater (Derbyshire), Zak Chappell (Leicestershire), Joe Clarke (Worcestershire), Dan Christian (Overseas - Vitality Blast)
Outs: Riki Wessels (Worcestershire), Billy Root (Glamorgan), Matt Milnes (Kent), Ben Kitt (Released), Will Fraine (Yorkshire)
Somerset
Ins: Jack Brooks (Yorkshire), Jerome Taylor (Vitality Blast), Azhar Ali (Overseas) Babar Azam (Overseas - Vitality Blast)
Outs: Fin Trenouth (Released), Johann Myburgh (Retired)
Surrey
Ins: Liam Plunkett (Yorkshire), Jordan Clark (Lancashire), Dean Elgar (Overseas), Imran Tahir (Overseas - Vitality Blast), Aaron Finch (Overseas - Vitality Blast)
Outs: Matt Pillans (Yorkshire)
Sussex
Ins: Rashid Khan (Overseas - Vitality Blast)
Outs: Stuart Whittingham (Gloucestershire), Mir Hamza (Overseas)
Warwickshire
Ins: Liam Norwell (Gloucestershire), Craig Miles (Gloucestershire), Ashton Agar (Overseas - Vitality Blast)
Outs: Jonathan Trott (Retired), Grant Elliott (Retired), Sunny Singh (Released), Chris Wright (Leicestershire), Josh Poysden (Yorkshire), Keith Barker (Hampshire), Andy Umeed (Released), Boyd Rankin (Released)
Worcestershire
Ins: Riki Wessels (Nottinghamshire), Wayne Parnell, Martin Guptill (Overseas - Vitality Blast)
Outs: Joe Clarke (Nottinghamshire), Steve Magoffin (Retired)
Yorkshire
Ins: Josh Poysden (Warwickshire), Matt Pillans (Surrey), Will Fraine (Nottinghamshire), Duanne Olivier.
Outs: Jack Brooks (Somerset), Andrew Hodd (Retired), Liam Plunkett (Surrey), Azeem Rafiq (Released), Alex Lees (Durham)