How to Write a Letter for Change of Address
If you want to write a letter to alert your contacts that your address is changing, open it with a brief paragraph that tells the recipient why they're getting the letter. Try writing “This letter is to advise you that my address will be changing soon.” Your letter should be under a page, so avoid being wordy. After your introduction, let the reader know exactly when your address will change and list the new address in the same format it should be used on an envelope. Next, include any extra information they should know. For example, if your business is staying open during the move, let your customers or suppliers know so they can plan in advance. Finally, close the letter by thanking the reader and giving them a phone number or email address where they can contact you.
Look for a business letter template. If you're typing your letter on your computer, check for templates in the word processing application you're using. Most word processing apps have a number of different letter templates. Use a basic business letter template that has blocks for the date, your address, and the address of the recipient. If you have business or personal letterhead that you plan to use to print your letter, make sure the template you use has room to accommodate that. Create a mailing list. The easiest thing to do, especially if you are sending your letter to a long list of recipients, is to create a mailing list on a spreadsheet. You can then use the "mail merge" function on your word processing app to populate the fields on your form letter. Set up address blocks. The traditional business letter format includes a block for your name (or your business's name) and address, as well as the name and address or the recipient. When you enter your address, use your current address, not the one to which you're moving. If you're using mail merge, follow the formatting guidelines set forth in your word processing app. Typically this means enclosing in brackets the name of the column from which you want the app to pull data from your spreadsheet, such as "firstname lastname." Provide a greeting. Your letter template typically includes a double-space after the last line of the last address block, followed by a greeting. It may simply be the person's name followed by a colon, or "Dear" followed by the person's name and a comma. Avoid using the "Dear" greeting if some of your recipients are organizations, other businesses, or government agencies. Typically this greeting is only used for individuals. Complete your closing. When formatting your letter, it's typically best to go ahead and get your closing down first and then draft the body of your letter. The word you use in closing will depend on your relationship to the recipients.  If you're writing a letter for change of address of your business, you'll want a more formal closing, such as "sincerely." However, if you have a mix of personal and business contacts, you may want to go with something less formal, such as "thanks." Write a brief introduction. Start your letter with a statement to inform the recipient of the letter's purpose. This doesn't have to be long. Typically a single sentence that says something like "This letter is to advise you that my address will be changing soon" will suffice. Don't get too wordy with your introduction. You want to keep the letter under a page, so it should be brief and to the point. Provide a date when the change will take place. Along with your introduction, you need to let your recipients know exactly when they need to start using your new address rather than your current one.  Make sure you're giving your recipients enough time to receive the letter, update their records, and get any letters out to the proper address. List your new address. Provide your recipients with the new address they should use for all correspondence with you in the future. Typically it's best to format it the way it should be formatted on the envelope, so it's easy for them to note and copy. Include any other relevant information. Depending on the circumstances of your move, there may be other information that your recipients need to know, such as if others also are moving with you, or whether your business will remain open during the move. Thank the recipient. To close your letter, double space after your last paragraph and write a simple sentence thanking the recipient. If they are a business associate, you may want to also add a note about how you appreciate their business. For example, if your business is relocating, you might write "Thank you for your attention to this matter. I greatly appreciate the value you add to this company and look forward to continued work with you." Provide a means of contact. After you thank the recipient, you may want to provide a phone number or email address the recipient can contact if they have any questions or concerns. This is especially important if your business is relocating. You may want to route all questions or concerns about the relocation to a particular phone number or extension, or to a particular email address. Craft several letters. Especially if you're relocating your business, you may want to have more than one letter. That way you can tailor one letter specifically to clients or customers, another to business associates, and another to vendors or dealers. Consider several letters if you have any relevant information you want to include that only applies to one audience. This way no one is getting any information other than what they need. Proofread your letter carefully. Before you finalize your letter, check to make sure there are no typos, spelling, or grammatical errors that make your letter look unprofessional or make it difficult to read. Check the address in particular and make sure it's correct. You don't want to send your recipients a change of address letter that points them to the wrong address. Make sure the recipients' information is correct. When you use mail merge for bulk mailings, it can save you a lot of time. But it's also possible that there may be errors in how the data is transferred to your letters.  Check all the fields and make sure they all match and belong to the same recipient. For example, you want to make sure that the name and address of the recipient in the address box matches the name in the greeting. Print and sign your letters. Once you're satisfied that your letters are formatted correctly and are error free, print them on good stock paper and sign them by hand using blue or black ink. Then they're ready to mail. Provide your recipients with advance notice. In most cases, you want to make sure your recipients will get their letters within two to four weeks prior to the date your change of address takes effect.  If you have international contacts, you probably want to provide two or three months' advance notice to allow for the time it takes to send mail internationally. 
Look for a business letter template. Create a mailing list. Set up address blocks. Provide a greeting. Complete your closing. Write a brief introduction. Provide a date when the change will take place. List your new address. Include any other relevant information. Thank the recipient. Provide a means of contact. Craft several letters. Proofread your letter carefully. Make sure the recipients' information is correct. Print and sign your letters. Provide your recipients with advance notice. 