Watford will be releasing five players this summer but are hoping to secure the futures of Martin Taylor and Stephen McGinn.
Goalkeeper Rene Gilmartin, defender Tom James, midfielder Chez Isaac and winger Michael Bryan were all out of contract this summer and the club have confirmed they will not be handing them extensions. Josh Walker had previously agreed a move to Scunthorpe United, where he has spent the second half of the season on loan.
Taylor and McGinn are also out of contract this summer but the Hornets are in talks with the pair over a new deal.
Watford manager Sean Dyche told the club's website: "The harsh realities of football are never far away - and for us as a club it means we simply cannot retain every player on our staff, despite all these lads having given everything to the club this year.
"We've valued their contribution to the squad throughout this season. They've been part of a group that's always looking to improve.
"On behalf of everyone connected with Watford, I'd like to them all well for their future in football."
Gilmartin, 24, joined the Hornets from Walsall on a free transfer last summer but only made seven appearances for the Hornets first team and spent most of this season on loan at Yeovil Town and Crawley Town.
James's rise is a quite remarkable one but his dream year has ended in disappointment. The left back joined last summer from Stratford Town in the Midlands Football Alliance, which is the ninth tier of English football and four stages below the Conference.
The 23-year-old was initially handed a six-month contract but it was extended until the end of the season in January and he made his professional debut a few days later.
Isaac is a combative midfielder who captained the Under-18s last season but due to the number of central midfielders at Watford, spent the majority of this season on loan at Boreham Wood and Tamworth.
Bryan was part of the first team squad in recent years; making eight appearances in the 2009/10 campaign and seven last season. But he has spent considerable time away from London Colney in the last year on trial at other clubs and on loan at Bradford City.
Walker agreed a move to Scunthorpe permanently two weeks ago after spending the second half of this season on loan at The Iron. The former Middlesbrough midfielder, 23, made just one start and six substitute appearances for the Hornets following his move two years ago.