Date of birth
The experienced striker has netted almost 200 goals in his career spanning 15 years.
He linked up with Neal Ardley's side in January 2019 after earning promotion from League Two with Wycombe in the previous season.
Mackail-Smith started his career with Dagenham and Redbridge but made his name during the first of three spells with Peterborough, scoring 80 league goals.
He also had stints with Brighton and Luton before joining Wycombe, who loaned him to Notts for the remainder of 2018-19.
Mackil-Smith hit the winner against Mansfield on 16 February as the Magpies ended their long wait for victory in the Nottinghamshire Derby.
Home kit: NCFCOSA
Away kit: Creative Apostrophe
Boots & socks: Available