Schedules with Open Modifications

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Contractor Login

The contractor login is specifically for contractors to complete a contract modification.

All first time users of this application are required to
register for Multi-Factor Authentication.

Registration is required for anyone that previously used the Mass Mods
application or any contractor who is new to this application.
Select the Register button below to proceed.

Mass Mods Multi-Factor Authentication User Guide

Welcome to Mass Mods

We have recently implemented new Multi-factor authentication
(MFA) process, so you may notice a different experience the
first time you log in.

Follow these steps to continue:

1. Before you login, make sure you already activated your account
through the activation email you may have received when you
registered your account.

2. Click on Contractor Login button.

3. Enter your email address and password associated with your
activated account.

4. You will be asked to send a verification code to your email
or to your preferred selected device you chose during your
account activation process.

5. Check your email / phone for the 6 digit code and enter on the
Verify code screen.

alert If you didn't receive an email, check the spam filters set up by your email
provider. You may also click the "Re-send code" link when available
to send another code.

		This is a U.S. General Services Administration Federal Government computer system that is "FOR OFFICIAL USE ONLY". By using this system you acknowledge: this system is subject to monitoring. Unauthorized attempts to upload information, view information, or change information of other vendor's data and attempts to bypass authentication or authorization mechanisms to gain access into unauthorized areas of the website and any other actions that would compromise the confidentiality, integrity, and availability of this system are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act.

Need Help?

For further assistance, please contact:
eOffer/eMod Helpdesk
Email: eoffer@gsa.gov
Phone: 1-866-472-9114

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