To inform one of; to say; to state; to communicate; to advise one of; to bring to one's notice (knowledge); to lay before one; to point out; to indicate; to mention; to apprise one of; to announce; to remark; to call one's attention to; to remind one of; etc.
1. We are pleased to inform you that
2. We have pleasure in informing you that
3. We have the pleasure to apprise you of
4. We have the honour to inform you that (of)
5. We take the liberty of announcing to you that
6. We have to inform you that (of)
7. We have to advise you of (that)
8. We wish to inform you that (of)
9. We think it advisable to inform you that (of)
10. We are pleased to have this opportunity of reminding you that (of)
11. We take the advantage of this opportunity to bring before your notice
12. Please allow us to call your attention to
13. Permit us to remind you that (of)
14. May we ask your attention to
15. We feel it our duty to inform you that (of)