There were ten religious houses dependent on Lewes, eight in England and two in Normandy. Some of these were substantial priories and others small cells. The Monasticon Anglicanum 1825 is a rich source of information on the abbeys and monasteries of England and Wales, albeit before more recent scholarly enquiry. There are entries on all the English daughter houses of Lewes Priory.
Priory of Castle Acre, near Swaffham, Norfolk, founded by William de Warenne, 1st Earl of Surrey, about 1087 and dedicated to St Mary. Surrendered to the Crown in 1537. William's wife died at Castle Acre in 1085.
It is now an English Heritage property.
Castle Acre website
British History Online entry
Castle Acre also had dependent houses:
Priory of Bromholm founded in 1113 by William de Glanville and dedicated to St Andrew.
Cell of Slevesholm (also known as Methwold) founded in 1140 by William de Warenne, 3rd Earl of Surrey and dedicated to the the Blessed Virgin and St. Giles.
Priory of Mendham, Suffolk, was founded by William de Huntingfield before 1155 and dedicated to the Virgin Mary. After the dissolution it became a private residence which fell into decay and was eventually demolished in 1815.
Priory of Normansburgh founded about 1160 by William de Liseurs and dedicated to the Blessed Virgin and St John the Evangelist.
Priory of Prittlewell, Southend, Essex, founded probably in 1110 and dedicated to the Virgin Mary by Robert fitzSweyn, who had received great land holdings from Edward the Confessor. He later gave the Priory to Lewes. After the dissolution it remained in private hands until it became the first museum of Southend in 1922.
British History Online entry
Priory of Stanesgate, Steeple, Maldon, Essex, founded in 1112 by Ralph, son of Brian, and dedicated to St Mary Magdalen. It was dissolved in 1525 by an agent of Cardinal Wolsey when there was only the prior and two monks. The church was used as a barn but there is now little remaining above ground.
Priory of Farleigh, Monkton Farleigh, near Bath, Somerset, founded probably by Maud, wife of Humphrey de Bohun, in 1125 and dedicated to St Mary Magdalen. At the dissolution there were only six monks and the property passed to the Dukes of Somerset under whose ownership it became Monkton Farleigh Manor.
Priory of Horton, near Ashford, Kent, founded about 1142 by Robert de Vere and dedicated to St John the Evangelist. At the dissolution many of the buildings were demolished and the remainder became a private house.
There were two dependencies of Lewes in Normandy but information about them is scarce. Both were relatively poor with only a prior and one or two monks. It is thought that Mortemer was founded in the 11th and Etoutteville in the 12th century. They remained attached to Lewes until the loss of Normandy left them under the rule of France.