The former Prime Minister is formally styled ‘The Most Honourable’ when he/she is a member of the Order of the Nation and ‘Mr’ when he/she is not.
(When he/she is a member of the Order of the Nation)
The Mode of Address in:
Writing:
The Most Honourable Portia Simpson Miller, ON
Address
Opening Salutation:
‘Dear Mrs. Simpson Miller,
Closing:
……………………………………………………………………………..
Yours faithfully (formal usage)
Yours sincerely (semi-formal usage)
Signature’
When referring to her and her spouse jointly, they are formally styled, ‘The Most Honourable Portia Simpson Miller and The Most Honourable Mr. Miller’.
(When he/she is a not member of the Order of the Nation)
Writing:
Mr Bruce Golding
Address
Opening Salutation:
‘Dear Mr Golding,
Closing:
……………………………………………………………………………..
Yours faithfully (formal usage)
Yours sincerely (semi-formal usage)
Signature’
The widows/widowers of former Prime Ministers are referred as per example below:
‘The Most Honourable Mrs. Edward Seaga’ and not ‘The Most Honourable Mrs. Carla Seaga’
Other examples
1) The late Right Honourable Hugh Lawson Shearer is now formally styled, ‘The late Most Honourable Hugh Lawson Shearer, ON, OJ’ or when appropriate, ‘The late Most Honourable Hugh Shearer’
The style of address for his spouse is, ‘The Most Honourable Mrs. Hugh Shearer, OJ, CD’. In her professional capacity, she is styled ‘The Honourable Professor Denise Eldemire Shearer, OJ, CD’
2) The late Honourable Michael Manley is now formally referred to as ‘The late Most Honourable Michael Norman Manley, ON, OM, OCC; or when appropriate ‘The late Most Honourable Michael Manley’
His widow is now formally styled, ‘The Most Honourable Mrs. Michael Manley’ and not ‘The Most Honourable Mrs. Glynn Manley’
3) The late Sir Donald Sangster is now formally referred to as ‘The late Most Honourable Sir Donald Sangster, ON, KCVO’.