Purchasing: Working with the County

You will receive emailed notifications of bid opportunities based on the commodity category codes you select during the registration process.

Registration in the Supplier Portal does not guarantee the receipt of electronic notification for all applicable solicitations.
Suppliers should routinely check our Supplier Portal for a list of current business opportunities. County of Sonoma Suppliers are responsible for self-managing and updating their accounts online.

Accounts should be checked regularly to assure your company’s contact information and category code selection is up to date.

Have your Taxpayer ID number or SSN on hand.

Navigate to the Supplier Portal. We recommend you open the Bidder Registration Instructions in a new window, or print them to use during registration.

Register as a Bidder and follow the registration instructions.

Please be sure to review and select appropriate commodity category codes.

If you registered with the County before July 1, 2014, you are not registered in our new system. Please register in the new Supplier Portal in order to receive emailed bid notifications.

• Have your Taxpayer ID or Social Security Number on hand, along with your current Vendor ID number. If you no longer have your Vendor ID number available, please email our Supplier Desk.
• Navigate to the Supplier Portal. We recommend you open the Supplier Registration Instructions in a new window, or print them to use during registration.
• Click on Register as a Supplier and follow the registration instructions. Please be sure to review and select appropriate commodity category codes.

If you registered in the new system after July 1, 2014, you do not need to re-register. However, you do need to log in to the Supplier Portal and update your account.

• Navigate to the Supplier Portal. We recommend you open the Supplier Account Management link in a new window, or print out to use during registration.
• Login with your User ID and password. If you have misplaced them, send an email to our Supplier Desk. When you receive your User ID, reset your password using the link on the Supplier Portal and login.
• In order to receive emailed bid notifications, you must edit existing contacts, designate a contact to receive emailed bid notifications, and select category codes for the goods and/or services you offer.

• Review bidding opportunities and place bids
• View invoices, payments, account balances, and purchase orders
• Update your company contact information, including email addresses
• Set up additional user accounts for employees based on the type of access your business requests

Please send an email to our Supplier Desk at supplier-desk@sonomacounty.gov.

The Single/Sole Source Purchases Report reflects total purchases from April 1, 2026 - June, 30, 2026. The total number and spend reflects the total number of payments made for this time period in comparison to Single/Sole Source Purchases for the period. 

California Government Code § 84308, commonly referred to as the "Levine Act," prohibits an officer of a local government agency from participating in a proceeding involving a contract, license, permit, or other entitlement for use if the officer accepted, received, or solicited a campaign contribution exceeding $500 from a party or participant, including their agents, to the proceeding within the prior 12 months.  It also requires that parties and participants to those proceedings, including their agents, affirmatively disclose their contributions on the record at the time of application or proposal, or within 30 days of making the campaign contribution if the contribution is made after submission of the application or proposal.

A “license, permit, or other entitlement for use” includes the approval of contracts exceeding $50,000 in value but excludes contracts that are required by law to be awarded to the lowest responsible bidder, such as public works contracts.  A “party” is any person, company, or organization that files an application for, or is the subject of, a proceeding involving a contract license, permit, or other entitlement for use. The contributions of a party must be aggregated with those of their agents and business entities majority owned by that individual. This means, for example, that if an individual’s company, organization, or other legal entity submitted a campaign contribution, individually or jointly exceeding $500, but the individual is the recipient of the potential benefit, the Levine Act requires a disclosure form to be submitted.  A “participant” is a person who actively supports or opposes a particular decision in a proceeding involving a license, permit, or other entitlement for use and has a financial interest in the decision.  Proceedings include the consideration of bids/proposals and the award of a contract pursuant to a Request for Proposals issued by the County.

If you qualify as a “party” or “participant” to a County proceeding subject to the Levine Act and you have made a campaign contribution exceeding $500 within the last 12 months to a Member of the Board of Supervisors, or other elected County officer, you must disclose the campaign contribution as part of your submission of a proposal through the Supplier Portal.  Contractors and suppliers should obtain legal counsel to determine whether campaign contributions made by the party seeking to contract with the County, or their agents, are subject to Levine Act disclosure requirements.

Submit Levine Act Disclosure Form here: sonomacounty.gov/levineactdisclosure