Electronic Invoicing

Electronic invoicing with the Maryland Procurement Office (MPO) provides a fast and accurate method of submitting and tracking invoices. All vendors are required to submit their invoices electronically through our MPO office, unless otherwise stated in the contract.

The MPO Electronic Commerce (EC) office has a secure website that allows vendors to submit invoices and attachments. The website is the only form of electronic submission of invoices. According to the DFAR for Electronic Submission and Processing of Payment Requests, fax, email and scanned documents are not acceptable electronic forms.

MPO understands that there could be circumstances that prevent vendors from submitting invoices electronically. MPO requests that any contractor/vendor who has compelling circumstances that necessitate continuation of hardcopy invoice submissions substantiate that need in a letter addressed to the cognizant contracting officer. Hardcopy invoices will be authorized on a very limited basis and only when there are compelling circumstances which also must be substantiated within the initial proposal submission. Please be advised that the submission of a letter requesting approval to submit hardcopy invoices does not guarantee MPO approval. MPO approval is contingent upon review and concurrence of the compelling circumstances contained within the letter.

Types of Invoices

The MPO website has the capability of accepting the following documents:

  • Commercial Invoices
  • Public Voucher SF1034, SF1035
  • Source DD250
  • Destination DD250
  • College Tuition DD1556

Note: All invoices requiring Office of Naval Research (ONR) approval must be submitted to ONR in hard copy form via mail. Once the invoices have been approved by ONR, they can be faxed, mailed, or emailed to MPO.


Vendor Requirements

A Department of Defense (DoD) IECA PKI Certificate is required to access the website. PKI certificates are used to identify web clients and to encrypt user sessions and emails so that private business stays private. EC complies with the DoD mandate that all private industry partners, contractors, allied partners, and other federal and DoD Agencies employ DoD certificates for all electronic communications.

The type of Certificate that our site requires is the ECA, Medium Assurance Digital Signature Non Repudiation Certificate. Two companies offer the certificate: 

The certificates range in cost from $100-$300, and they are good from one to three years. When you go to any of these sites, ensure that you are choosing the correct certificate. You want the ECA, Medium Assurance Digital Signature Non Repudiation Certificate. On the IdenTrust website, look for "Medium Assurance" certificate. You will have to fill out their application and mail it in. The company will send the certificate to you via email. They should also include instructions on how to download the certificate to your computer.

Once you have received your certificate and loaded it into your web browser, please inform the EC Office. The EC office will download your public key and create and account for you to log in.

The Invoicing Process

  • Submitting an Invoice: 

    Submitting an invoice is easy. All you have to do is fill out all of the necessary fields on the invoice form. You select the option to create an invoice from scratch or from templates. Fill in the mandatory information at a minimum such as the contract number, invoice number, dates, line items (CLIN/SLIN/ACRN) and Final invoice (Yes/No) and then click the Submit button. You can also attach an Excel, Word, Adobe PDF, PowerPoint or Access file to accompany your invoice.
  • Invoice Processing: 

    Upon hitting the Submit button, the invoice will be captured by the eCommerce system. The invoice is uploaded into the Accounts Payable (AP) Financial system twice a day. The system will perform a number of validations to verify that the invoice is proper. If errors are present such as wrong contract number, incorrect CLIN/SLIN/ACRN combination and/or duplicate invoice number, the system will automatically send a rejection email to the company's point of contact.

    Once the invoice has been successfully uploaded into the AP Financial system the EC team sends an email with the invoice and all attachments to the AP team. The AP team forwards the invoice files to the Contract Officer Representative (COR) for invoice certification (approval or rejection of invoice). The AP team and COR perform a thorough analysis of the invoice based on the contract clauses, federal invoicing rules and regulations. The COR is able to log into the system, review the invoice and attachments and possibly approve or reject the invoice. Upon certification/rejection, an email is sent to the responsible Accounts Payable Technician informing them of the status of the invoice. At that time, the AP Technician is able to process the invoice for payment taking into consideration the Prompt Payment Act providing MPO 30 days to pay the invoice from date of invoice receipt.
  • All Cost Reimbursable and Time and Material invoices have to be certified by the Defense Contract Auditing Agency (DCAA). All electronic invoices regarding these types of contracts have to be routed to the DCAA representative before they are sent to the AP team. The DCAA Representative has 5 working days to certify the invoice and send it to the AP team electronically via eCommerce. If these types of invoices are received by the AP Technician without a prior DCAA approval, the invoices will be rejected automatically.

Note: When an invoice is submitted electronically, please do not provide paper copies (mail, fax, email, etc.) to anyone here at MPO.

Vendor Notification

  • Invoice Pending:

    When an electronic invoice is submitted, the next business day the vendor starts receiving an Invoice Pending email informing them that their invoice has been received and it is waiting for COR action.

  • Invoice Status:

    When the status of an invoice is changed by the COR (certified or rejected), an email is sent the next business day informing the vendor of the change. If the COR rejects the invoice, a rejection letter is also sent to the vendor via email.

  • Invoice Payment:

    When the invoice is paid, an invoice payment email is sent to the vendor.


  • ​5 CFR 1315 - Prompt Payment Act
  • DFARS 242.803 - DCAA
  • US Code Title 10 Section 2227 - Electronic Submission and Processing of Claims for Contract Payments
  • DoD8190.2 The Department of Defense (DoD) Electronic Business/Electronic Commerce (EB/EC) Program


The MPO website is available all day every day. EC Help Desk Representatives are available Monday - Friday from 7 a.m. to 4 p.m. Eastern Time (ET) at (410) 854-5445. AP Customer Service Representatives are available Monday - Friday 8 a.m. to 3 p.m. ET by phone at (443) 654-3700 or email us.

Contact the Electronic Commerce Office for questions at (410) 854-5445 or by email