Notts Outlaws will begin their defence of the T20 Blast trophy with a home game against Birmingham Bears – in a repeat of the 2017 final.
The 2018 competition will start on Wednesday 4 July, with the group stage running until Friday, 17 August.
The quarter-finals will be played from 23-26 August and Finals Day, again staged at Edgbaston, is on 15 September – two weeks later than in 2017.
County Championship and One-Day Cup fixtures will be released on Wednesday.
Notts hope Australian all-rounder Dan Christian will return to captain their T20 side again, although that is still to be confirmed, and the Bears will be led by New Zealand’s Grant Elliott, who took on the job from Ian Bell midway through the 2017 competition.
“We get great support at Trent Bridge so it’s great to have a home game for our first game as champions, and a repeat of last year’s final against the Bears means it will be a big game for both teams,” said Notts all-rounder Steven Mullaney.
The re-match between the 2017 finalists is one of three fixtures on the opening day of the 2018 tournament.
Northants, winners in 2013 and 2016, will play Leicestershire, the only side to lift the trophy on three occasions, at Wantage Road, and Essex Eagles will face Sussex Sharks at Chelmsford.
Opening T20 Blast fixtures in 2018
Wednesday, 4 July
Essex v Sussex, Chelmsford
Northamptonshire v Leicestershire, Northampton
Notts Outlaws v Birmingham Bears, Trent Bridge
Thursday, 5 July
Lancashire v Worcestershire, Old Trafford
Middlesex v Surrey, Lord’s
Yorkshire v Durham, Headingley
Friday 6 July
Derbyshire v Lancashire, Derby
Essex v Middlesex, Chelmsford
Hampshire v Glamorgan, Ageas Bowl
Leicestershire v Durham, Leicester
Northamptonshire v Notts Outlaws, Northampton
Somerset v Gloucestershire, Taunton
Surrey v Kent, The Oval
Worcestershire v Birmingham Bears, Worcester
Who plays who?
North group: Birmingham Bears, Derbyshire Falcons, Durham Jets, Lancashire Lightning, Leicestershire Foxes, Northamptonshire Steelbacks, Notts Outlaws, Worcestershire Rapids, Yorkshire Vikings.
South group: Essex Eagles, Glamorgan, Gloucestershire, Hampshire, Kent Spitfires, Middlesex, Somerset, Surrey, Sussex Sharks.
Fixtures by county
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Source: BBC Here