How to order ZP4 service

  • Prepayment is required.
  • Use our online order form to place an order using a credit card.
  • Generate an invoice if you wish to submit a check or if your accounts payable department requires a bill.

    Terms and conditions

    1. RATE: ZP4 processing is currently $1 per 1,000,000 bytes of input/output.

    2. PAYMENT: ZP4 service is prepaid. The minimum payment is $29 (29 megabytes of transactions). Only MasterCard, Visa, American Express, and checks are accepted for payment. Allow 24 hours for the processing of submitted payments, although orders placed during normal business hours are usually processed the same day.

    3. MAINTENANCE: Every 30 days after the creation of any account (except for client accounts that share a master account) a $9 fee will be deducted from the account's balance. This fee is not refundable. The fee is prorated before any terminated account is closed.

    4. CANCELLATIONS AND REFUNDS: During the first 7 days an initial order is active, new ZP4 users can receive a money-back guarantee on their purchase. After that, or from the start of any subsequent order, any paid but unused balance canceled by the customer is subject to a 7% order cancellation charge. If you terminate your service and close your account to stop the 30-day maintenance fee, then open a new account at a later date, a $25 fee will apply. Semaphore Corporation reserves the right to cancel and refund the unused balance for any account at any time.

    5. TRANSFERS: Transfers of unused balances from one account to another upon receipt of validated requests are free.

    6. EMAIL: Your email address is only used to send you a payment receipt, account activation notices, and notification of Postal Service™ database or software changes. Semaphore Corporation will not distribute any of your account information to any other party.

    7. RATE CHANGES: After 30 days notice, ZP4 processing rates and fees for an account's unused balance are subject to change.

    8. LICENSE: Use of ZP4 is subject to a license you accept when installing the software.

    9. POSTAL SERVICE VIOLATIONS: The Postal Service prohibits using their data to generate address lists (for example, by testing every possible house number on a street to determine the valid addresses). Such activity will result in the termination of your account.


    Go to the ZP4 home page.
    Semaphore Corporation is a non-exclusive licensee of the United States Postal Service®. The prices of Semaphore Corporation services are not established, controlled or approved by the Postal Service™. The following trademarks are owned by the United States Postal Service: Postal Service and United States Postal Service. [DA#10.07]