Why not just use mail-merge software on my computer?

You can do that. But consider:

  • You need to own the proper software, such as a full install of MS Office (Word/Excel/Outlook).
  • You need to figure out how to set up mail merge. Unless you do mail-merge frequently, it's a lot more time-consuming than using maillists.com.
  • You can't schedule a mailing time, you must start it manually.
  • You can't schedule multiple mailings.
  • Soon after you click send, you will probably discover that your ISP or mail server has a limit on how many emails you can send per hour or per day. Your mailing is likely to be interrupted. Restarting without sending duplicate messages can be difficult.
  • You will need to handle opt-out requests and bounces yourself and diligently keep your spreadsheets current to avoid being labeled a spammer.
  • Messages you send yourself won't have desirable SPF and DKIM headers which help enhance deliverability.
  • If you have a list of more than a couple of hundred contacts, it may take a long time to send all the messages via mail-merge.
  • To send to more than one group of contacts, you must first consolidate them into a single spreadsheet.
  • You can't easily exclude a group of contacts. Instead you need to remove unwanted addresses from your target spreadsheet before you start the mail-merge operation.
  • Mail-merge doesn't automatically eliminate duplicate addresses.
  • maillists.com service includes helpful advice if/when you need it, from folks who have a lot of experience sending email.