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Certified Mail Software for Accounting Firms and CPAs

IRS “mailbox rule” encourages Certified Mail use for important deadlines

When it comes to sending time sensitive documents, accounting firms and certified public accountants (CPAs) often use Certified Mail. This USPS service offers tracking and signature upon delivery when accounting firms send important documents such as monthly invoices, collection notices and IRS tax documents.

Certified Mail's Role in Accounting Communications
Accounting firms use Certified Mail because the USPS service includes a tracking number, allowing the sender to know exactly when their item has entered the mailstream and when the item has been delivered. Certified Mail also includes signature confirmation upon delivery (Proof of Delivery) from the person who accepts the mail.

To obtain a signature, the sender must purchase a Return Receipt from the USPS at the time of mailing their Certified Mail. A Return Receipt may be done either electronically (via or physically (via postcard, for a slightly higher cost) and delivers a copy of the recipient’s signature to the sender. The signature from the Return Receipt provides proof that the mail was delivered or that an attempted delivery was made.‍

Prima Facie Evidence: Certified Mail and the IRS Postmark Date
When sending important documents such as tax payments and tax forms, accounting firms rely on Section 7502(c) of the IRS code, known as “prima facie evidence” or the “mailbox rule.”  The rule states that if the tax documents were sent using Certified Mail, the mailpiece will be deemed as delivered on the postmark date on the letter and/or post office receipt. This means that as long as your return is addressed correctly, has enough postage and most importantly, is postmarked by the due date, the IRS considers the tax return as filed on the date the mailpiece was sent.  The “mailbox rule” provides a huge incentive for tax filers to use Certified Mail to avoid penalties and interest fees when electronic submission is not an option.

Send Certified Mail Online Easily with Software
Accounting firms across the country, including two of the Big Four, use Certified Mail software from to make the preparation, tracking and management of Certified Mail more efficient. This service can reduce labor costs by more than 80%.

How can help:

  • No USPS forms: eliminates USPS forms (Green Cards) from the mailing process. Instead, you can print cover sheets and labels (for envelopes and packages) from any inkjet or laser printer at your home or office.
  • No trips to the Post Office: Avoid the busy Post Office. Drop your completed Certified Mail items in any USPS mailbox or leave them for your daily mail carrier to pick up.
  • Proof of Acceptance: For each Certified Mail item that receives its first outbound acceptance scan from the USPS, a Proof of Acceptance PDF is posted to your account. IRS and state tax agencies regard the Proof of Acceptance as the legal equivalent of USPS form PS 3800 with the red round date stamp, a USPS PS 3877 Form Mailing Book or a USPS Mailing Manifest.
  • Return Receipt Electronic: When a recipient’s signature is required, the USPS Return Receipt Electronic is posted to your account within 24 hours of your Certified Mail letter being delivered and the signature collected on the mail carriers tablet computer. No more waiting a week or more for Green Cards to come back or sending replacement Certified letters for those with lost Green Cards.
  • 10 Year Data Archive: The Proof of Acceptance, Return Receipt Electronic and production data including costs for each mailpiece, are retained in your account for 10 years. Production data makes it easy to summarize your expenses by client and seek reimbursement when appropriate.

Get started quickly!

Getting started is simple. There’s no software to install. No fixed monthly fees. Just a small transaction fee per piece, and we supply the Certified Mail window envelopes at no extra charge. Just tell us how many you need to get started and prefund your account (minimum level of $60). You’ll receive the envelopes in 3-5 days and unused funds are refundable. To sign up, click below. If you have questions, call 888-462-1750. 8am–5pm ET.

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