Commander and Lieutenant Commander
These ranks should not be abbreviated.
How to Address a Commander or Lieutenant Commander
The recommended social style of address is as follows:
|Beginning of letter||Dear Commander/Lieutenant Commander Jones|
|End of letter||Yours sincerely|
|Envelope||Commander John Smith, CBE, RN; Lieutenant Commander James Jones, RN|
|Verbal communication||Commander Smith*/Lieutenant Commander Smith
|Invitation||Commander John Smith/Lieutenant Commander James Jones
|Description in conversation||Commander Smith/Lieutenant Commander Jones|
|List of Directors or Patrons||Commander John Smith; Lieutenant Commander James Jones|
|Place card||Commander John Smith/Commander James Jones|
*A younger man, or a more junior officer in any of the Armed Forces, addresses him as 'Sir'.