Saying Thank You
Yes, you need to send a handwritten thank you note!
When a person was kind enough to give you a gift, their generosity should be rewarded with a sincere and enthusiastic thank you note.
Be prompt. Try and send the note within 10 days of receiving the gift.
Be sincere. Use words that you are comfortable with and would use when speaking.
Be specific. Always mention the gift by name, and if the gift is money, mention what you intend to purchase with it.
If you have questions about invitation etiquette, letter-writing, electronic vs hand-written correspondence, or all things paper, send them along to Since You Asked.

