England captain Joe Root will miss Yorkshire's first two matches of the County Championship season following the Test series defeat in New Zealand.
The 27-year-old, along with team-mate Jonny Bairstow, can play against Essex (4 May) and Surrey (11 May).
Paceman Stuart Broad will be available for Nottinghamshire from 27 April after missing their first two games.
The England management are yet to decide on the early-season availability of Lancashire seamer James Anderson.
However, six England players have been cleared to play in the first four matches of the first-class season.
Hampshire batsman James Vince, new Lancashire captain Liam Livingstone, Somerset bowlers Jack Leach and Craig Overton and Surrey pair Ben Foakes and Mark Stoneman have been cleared to play for their respective clubs without a break.
Essex opener Alastair Cook and Dawid Malan, the new Middlesex skipper, are eligible to play three of the first four games for Essex and Middlesex respectively.
But champions Essex will be without Cook when they begin the defence of their Division One title against Yorkshire at Headingley.
The 2018 season starts on Friday, 13 April with three games in the top flight and a further three in Division Two.
Moeen Ali (Worcestershire), Jos Buttler (Lancashire), Jason Roy (Surrey), Ben Stokes (Durham), Chris Woakes (Warwickshire) and Mark Wood (Durham) will all miss the start of the domestic season after signing deals to play in the Indian Premier League.
The full list of early-season player availability is available via the England & Wales Cricket Board website.