Welcome to EMEP’s Vendor Relations Site.

Our goal is to provide you with access to your information and to help you answer frequently asked questions. 
On this page you will find:

We understand that not all questions can be addressed online.  At the bottom of this page, you will find our contact information in case you need to reach us directly.

OpenInvoice Login

To be in line with our business strategy, we request that all invoices are submitted electronically through OpenInvoice to Eagle Mountain Energy Partners.  The correct customer site is EMEP Operating, LLC.

If you are not a registered user of OpenInvoice, you can sign up by going to the registration site and then email supplieronboarding@enverus.com to complete your setup.

If you are registered with the OpenInvoice network, go to www.openinvoice.com to login and submit your invoice.

Frequently Asked Questions

Once you have logged into OpenInvoice, there are videos available by clicking on the help button on the top right of the screen. Go to Supplier Training Videos to learn how to use the system.

If you are still having issues with OpenInvoice, please contact OpenInvoice Support at openinvoicesupport@enverus.com or call the support team at 1-866-627-3287.

Once you have logged into OpenInvoice, click on the help button on the top right of the screen. Go to Supplier Guidelines and click on the link for Eagle Mountain Energy Partners.  This document will show you the fields that are required to successfully submit an invoice.

To sign up for Direct Deposit Payments, please complete and sign the ACH Authorization Form and attach a voided check.

To receive a replacement check, please submit:

• Your Vendor Number.
• Your Legal Name.
• Your Mailing Address.
The invoice number(s) for the missing payment
The amount of the missing payment

For Change of Address or Bank Changes, please complete the appropriate form below and email us a signed copy.  For ACH changes, please remember to attach a voided check.

Change of Address Form
ACH Authorization Form

In accordance with IRS Guidelines, EMEP mails IRS 1099-MISC Forms by January 31st of each year.

If your company has changed names due to a merger, send us copies of:

• Certificate of Merger
• Executed W-9

Otherwise, send a copy of the Certificate of Name Change and an executed W-9.

Commonly Used Forms for Download

Vendor Contact Form

"*" indicates required fields

Max. file size: 512 MB.

Contacting EMEP

You can reach us by:

  • By emailing us at EMEP
  • By filling out our Web Form
  • Calling us at +1.833.201.5838.  If a team member is not available to take your call, please leave a message with your name, vendor number, return phone number and reason for calling.  We will respond back to you within 5 business days of receiving your message.
  • Mailing us at:
    EMEP Operating, LLC
    c/o EAG 1Source
    2628 Highway 36 S PMB 283
    Brenham, TX 77833-9616

Send us copies of all requested documents.  Originals will not be returned.

We look forward to addressing your questions and concerns.