Penmate Inmate Support Guides

Sending Mail to Someone at Maguire: The Smart Communications Address and How to Find Their SMCSO ID

To send personal mail to someone at the Maguire Facility, you'll address it to Smart Communications first. You'll also need the person's SMCSO ID number for the Attention line. Here's the exact format to use, plus the quickest way to look up that ID.

• 2 min read Verified from official sources

Personal mail for people housed at the Maguire Facility goes through Smart Communications, not directly to the jail. Your envelope needs to follow their specific addressing format so it gets routed correctly. The biggest cause of mail delays? Missing identification. Your mail needs an "Attention to" line that includes the incarcerated person's name and their SMCSO ID number, written together in the format the jail specifies.

Rule to follow every time: Address your mail with "Attention to (INMATE NAME - ID NUMBER)". If the ID number is missing, your letter may not be processed.

Copy this address format exactly: Smart Communications - San Mateo County Jail Attention to (INMATE NAME - ID NUMBER) P.O. BOX 9126 Seminole, FL 33775-9126

  1. Go to the San Mateo County inmate locator - This is where the jail directs you to obtain an SMCSO ID number.
  2. Search using both first and last name - The locator specifically instructs you to enter BOTH first name and last name to get results.
  3. Open the correct record and note the SMCSO ID - Use that SMCSO ID in your “Attention to (INMATE NAME - ID NUMBER)” line when you mail a letter.
  4. Consider registering for custody notifications - The locator also points people to California VINE for custody status changes and criminal case information, which can be helpful if you want updates.

Smart Communications also runs SmartInmate, an online system for communicating with someone who is incarcerated. Creating an account is free, and sign-up is quick. If you plan to use it, follow Smart Communications' sign-up steps so your information matches what the system expects.

Checklist Before Mailing

  • ✓ Use the required Attention format: Attention to (INMATE NAME - ID NUMBER)
  • ✓ Double-check the person’s name spelling and include their SMCSO ID number
  • ✓ Address the envelope to Smart Communications - San Mateo County Jail at P.O. BOX 9126, Seminole, FL 33775-9126
  • ✓ Include your own name and return address
  • ✓ Do not decorate the envelope in any way

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