The description of the characteristics of a livestock breed is commonly referred to as the Breed Standard. The characteristics define the breed allowing differentiation between other livestock animals of the species. They cover externally observable qualities. Breed standards help define the ideal of a specific breed. They can change and be updated over time.

Colour	Chesnut. No other colour is allowed. Historically 7 shades of chesnut were defined  Dark Liver, Dull Dark, Light Mealy, Red, Golden, Lemon and Bright. However The Society will accept   Liver, Dark, Red, Light, or Bright chesnut. Note   When referring to Suffolk horse chestnut is always spelled chesnut Whole-colour is preferred but a certain amount of white on the face is acceptable. A scattering of silver or white hairs on the body is allowed.  White to the fetlock is allowed but is regarded as a fault and is not acceptable for stallions being used for breeding. Hoof colour is not prescribed so will be either pigmented or unpigmented.
Height	Height range at maturity is between 15¾ hands and 17 hands.Note  There are instances of individual animals exceeding 17hh.
Head	Big with broad forehead but elegant, shapely and well proportioned.
Eyes	Well set, full, bright and intelligent.
Neck	Deep in collar tapering gracefully towards the setting of the head.
Shoulder	Long and muscular, well thrown back at the withers.
Girth	In proportion to height.
Back	Wide and level.Graceful outline in back, loin and hind quarters with tail well set up.
Fore-End	Broad in front. Great depth of heart with every appearance of strong constitution.
Hind-Quarters	Broad behind with good second thighs
Ribs	Deep round ribbed from shoulder to flank
Legs	Legs short in proportion to body.Fore legs straight. Pasterns well sloping at the same angle as the hoof, big flat knees and long clean hocks on short cannon bones.Elbows turned in are a serious defect as are straight hind legs.
Bone	Good flat bone with strength below the knee and hock.
Feet	Large strong feet circular in form protecting the frog. Wide coronet. Strong open heel.
Hair	Clean legged. Minimal hair allowed at heels
Action – Walk	Smart and true. Quick springing action with hocks kept fairly near together.
Action – Trot	Well balanced level movement with good straight action.

Colours

There are seven shades of chesnut described in the breed standards, but it is often very difficult to decide which shade a horse is, as they change in different seasons, different lighting conditions and with age, and so there is much debate about how useful this chart is. 

Colours and markings are noted carefully in passports to be able to identify individual animals, but with the advent of microchipping (now a legal requirement for ALL horses in the UK) there is less chance of mistaken identity!