- (St.) Mary Magdalen, Aldgate
- (St.) Mary Magdalen, Eldefisshestrete
- (St.) Mary Magdalen, Lamberdyshel
- (St.) Mary Magdalen, Milk Street
- (St.) Mary Magdalen, Old Fish Street
- (St.) Mary Matfellon
- (St.) Mary Mounthaunt Lane
- (St.) Mary Mounthaw
- (St.) Mary Mounthaw Churcbyard
- (St.) Mary of Graces, Abbey
- (St.) Mary of the Carmelite Friars
- (St.) Mary of the Piu
- (St.) Mary Olaf
- (St.) Mary Oldechurche
- (St.) Mary Pattens
- (St.) Mary Pellipar
- (St.) Mary Salutacion
- (St.) Mary Somerset
- (St.) Mary Spital
- (St.) Mary Staining
- (St.) Mary Street
- (St.) Mary towards the Tower
- (St.) Mary Upehulle
- (St.) Mary Wenlock
- (St.) Mary Whitechapel
- (St.) Mary within Cripplegate, Hospital of
- (St.) Mary Without Aldersgate
- (St.) Mary without Aldgate
- (St.) Mary without Bishopsgate, Hospital of
- (St.) Mary Wolmaricherch
- (St.) Mary Woolchurch
- (St.) Mary Woolnoth
- (St.) Mary, King's Chapel of
- (Sts.) Mary and Nicholas Chapel by the Tower of London
- Mary, Priorie of Elsing Spital
- (St.) Mary's Chapel in the New Churchyard near Smethefeld
- (St.) Mary's Chapel, Moorfields
- Masons' Alley
- Masons' Avenue
- Masons' Court
- Masons' Hall
- Massey's Court
- (St.) Matthew Friday Street
- (St.) Matthew Silver Street
- (St.) Matthew's Alley
- (St.) Matthew's Alley, Court
- (St.) Matthew's Buildings
- (St.) Matthew's Court
- La Maudelyne in Eldefihsstrete
- Maudlin's Rents
- Maul's Court
- May Square
- Mayden Alley, Aldersgate Street
- Mayden Lane
- Maydenhead Alley, Thames Street
- Maydys Hedde
- Mayegood Alley
- Mayors of London
- Maypole Alley
- Maypole Alley or Court
- McLean's Buildings
- Meal Market
- Meal Yard
- Mearmaid Alley, Warwick Lane
- Mede Lane
- Mediford Court
- Meermaid Court
- Meermaid Inn
- Meeting House Court
- Meeting House Yard
- Meeting House Yard, Gravel Lane
- Meeting House Yard, Miles' Lane
- Meigley's Court
- Melc Street
- Melk Street
- Mellin's Rents
- Melters of Tallow and Lard
- Menchenelane
- Menchonelane
- Menechine Lane
- Mengenelane
- Mengeoneslane
- Mengonelane
- Menionelane
- Menterhous
- Mercers' Chapel
- Mercers' Company
- Mercers' Court
- Mercers' Hall
- Mercers' Rents
- Mercers' School
- Le Mercersrent
- The Mercery
- Merchant Taylors
- Merchant Taylors' Alms Houses
- Merchant Taylors' Almshouses
- Merchant Taylors' Garden
- Merchant Taylors' Hall
- Merchant Taylors' Rents
- Merchant Taylors' School