A "thank you for joining" membership letter should include a personalized greeting to the new member. Use the member's first name in your salutation.I wanted to take a moment to reach out and send you my sincerest greetings. Governor JB Pritzker is glad to assist Illinois residents in honoring their accomplishments or celebrating milestones. Requests must be made at least 30 days. Here are 10 things your welcome letter or email to new members must include plus a template that can be customized for your organization. There are five required parts of a letter and one optional part. The five include a heading, greeting, body, closing, and signature. Try our free donation request letter templates! Download our standard template or check out our example letters for events, auctions, schools, and more.