The guests' names are written in the top left corner, except for formal luncheon and dinner invitations designed to include them in the middle of the card.
No prefixes, such as 'the Right Hon' or 'the Hon', are employed.
No letters after the name are included.
All peers and peeresses, apart from dukes and duchesses who are referred to by these titles, are given the form Lord and Lady Blank. This is the established custom for all but the most important private functions, when the exact rank in the peerage may be given.
Grown-up sons and daughters are usually sent separate invitations even when they live at home. However, when their exact names, or their availability, are not known, it is permissible to add 'and Family' after their parents' names.
The addition 'and Guest' or 'and Partner' may be added.
Note that, traditionally, invitations to a married couple, when sent to their home address, are addressed to the wife alone, with both names being inscribed on the invitation card. It has become increasingly acceptable, however, to address the envelope with both names.