Burns is one of three fly-halves named by Stuart Lancaster, with Toby Flood and Owen Farrell the others after Flood was cleared of a dangerous tackle charge late last night.
Lock Joe Launchbury, hooker Tom Youngs and prop Mako Vunipola join Burns in being formally promoted to the senior squad after they all played a big part in the autumn Tests at Twickenham.
The promotions mean Lancaster has widened his senior party from 32 to 33, with matchday squads this year having also been increased from 22 to 23 to allow for the inclusion of an extra prop.
Lions flanker Tom Croft is included after recovering from a serious neck injury, while fellow back rower James Haskell is preferred to Phil Dowson and Saracens wing David Strettle comes in for Charlie Sharlples.
Jordan Turner-Hall, Tom Palmer, Anthony Allen, Rob Webber, Mouritz Botha and the retired Matt Stevens all join Sharples and Dowson in dropping out of the main squad.
Wasps No8 Billy Vunipola, the younger brother of Maku, will train with England at their pre-Six Nations camp in Leeds as cover for Croft who only returned to action last Friday following an eight-month lay off, while the most notable additions to the second-string Saxons are rugby league converts Kyle Eastmond and Joel Tomkins and Wasps youngster Elliot Daly.
"This is a very important year for England, with the Six Nations and the Saxons games to look forward to so there are some great opportunities for the players to demonstrate their club form at international level," said Lancaster.
"The fact that we have spent significant time deliberating over quite a few players shows how tough the competition is and the strength in depth that is emerging.
"We have made some changes to both squads and we feel that reflects the players' form during the first half of the season.
"There will be undoubtedly be movement between the two squads as we go through the RBS 6 Nations and that was evident in the QBE Internationals, with players in form pushing through such as Freddie Burns, Joe Launchbury, Tom Youngs and Mako Vunipola.
"The summer tour to Argentina will also be a great chance for those players pushing for a place, especially with some of our senior squad hopefully going with the Lions, and chances will undoubtedly arise as we hope to play two midweek games as well as the two Tests."
The senior squad will attend a training camp at West Park Leeds RFC between Sunday, January 20 and Friday, January 25 before meeting up at Pennyhill Park in Surrey on Sunday, January 27.
The Saxons will meet up on Monday, January 21 at Harlequins' training ground at Surrey Sports Park ahead of their match against the Ireland Wolfhounds in Galway on Friday, January 25.
England senior squad
Forwards: C Clark (Northampton Saints), A Corbisiero (London Irish), D Cole (Leicester Tigers), T Croft (Leicester Tigers), D Hartley (Northampton Saints), J Haskell (London Wasps), T Johnson (Exeter Chiefs), J Launchbury (London Wasps), C Lawes (Northampton Saints), J Marler (Harlequins), B Morgan (Gloucester Rugby), G Parling (Leicester Tigers), C Robshaw (Harlequins), M Vunipola (Saracens), T Waldrom (Leicester Tigers), D Wilson (Bath Rugby), T Wood (Northampton Saints), T Youngs (Leicester Tigers)
Backs:C Ashton (Saracens), B Barritt (Saracens), M Brown (Harlequins), F Burns (Gloucester Rugby), D Care (Harlequins), L Dickson (Northampton Saints), O Farrell (Saracens), T Flood (Leicester Tigers), B Foden (Northampton Saints), A Goode (Saracens), J Joseph (London Irish), D Strettle (Saracens), M Tuilagi (Leicester Tigers), B Twelvetrees (Gloucester Rugby), B Youngs (Leicester Tigers)
England Saxons squad
Forwards: M Botha (Saracens), N Catt (Bath Rugby), L Deacon (Leicester Tigers), P Doran Jones (Northampton Saints), P Dowson (Northampton Saints), W Fraser (Saracens), J Gray (Harlequins), G Kitchener (Leicester Tigers), S Knight (Gloucester Rugby), M Kvesic (Worcester Warriors), M Mullan (Worcester Warriors), D Paice (London Irish), T Palmer (London Wasps), G Robson (Harlequins), E Slater (Leicester Tigers), H Thomas (Sale Sharks), B Vunipola (London Wasps)
Backs: N Abendanon (Bath Rugby), A Allen (Leicester Tigers), T Biggs (Bath Rugby), E Daly (London Wasps), K Eastmond (Bath Rugby), G Ford (Leicester Tigers), G Lowe (Harlequins), J May (Gloucester Rugby), U Monye (Harlequins), J Simpson (London Wasps), C Sharples (Gloucester Rugby), J Tomkins (Saracens), J Turner-Hall (Harlequins), C Wade (London Wasps), R Wigglesworth (Saracens)