Skip to Content
Doing Business with the County

General Information for Construction Contractors

State of California Contractor's License

We only hire state licensed contractors for construction projects regardless of size, scope, or dollar amount, and we confirm that the license is current and active with the State before issuing a Purchase Order or entering into a contract.

Supplier Registration

Registration ensures that your company, as well as the North Coast Builders Exchange, receives emailed bid notifications for the categories you indicate an interest in. Please register at the County’s Supplier Portal; step-by-step registration instructions are posted there.

All contractors are required to register and meet requirements of the Department of Industrial Relations (DIR) Public Works Construction Project regulations using the State of California online application.

Insurance Requirements

The Board of Supervisors has mandated an insurance level that we are not able to negotiate. All suppliers that perform services, particularly construction serves, must supply our office with acceptable certification prior to the start of any job. Our basic requirements include proof of General Liability with specific endorsement language naming the County as additional insured, Automotive, Worker's Comp and in some cases environmental pollution. All limits are $1,000,000. The name insured must match the name your Contractors license is issued in.

Prevailing Wage

State law requires that we pay prevailing wage on all construction projects over $1,000. Prevailing Wage rates may be obtained through the North Coast Builders Exchange or from the State Industrial Relations Department. The County reserves the right to require copies of payroll records, certified in accordance with the State of California Labor Code Section 1776.

Signature Authority

The Purchasing Agent is responsible for all projects valued at $0.00 to $200,000. We issue informal sealed bids for projects over $60,000. Contracts of $60,000 or more use the Sonoma County Construction Contract rather a purchase order. A Bid Bond, Performance Bond, and Labor and Materials Bond as well as insurance are all required on projects this size.

Projects less than $60,000

We can choose to do projects under $60,000 in-house, using County staff, or we can get quotes from licensed contractors. To expedite the quote process, the Architect or Facilities team usually contacts two to three contractors for competitive quotes.

Projects between $60,000 and $200,000

We issue informal sealed bids for projects between $60,000 and $200,000. These projects utilize the County’s informal bid list.

Notice Inviting Pre-Qualification Applications

Informal Bidding Qualification Application

Project over $200,000

Projects over $ 200,000 are Board bids and the Sonoma County Board of Supervisors will sign the resultant contracts.

Bid Package

Our bid packages include detailed job specifications and directions on what documents are to be included with the bid: how a bid will be awarded, what documents require a Notarized signature, and where to deliver the bid.

If at any time you need technical assistance, email the project manager at the email address listed in the bid package. They can assist you in understanding the document requirements. Procedural questions should be referred to the Purchasing Division.

If there are any changes made to the specifications, you will receive a written addendum. Do not bid based on a conversation with the project manager. Always bid based on what is written in the bid unless you receive a written addendum changing the specifications.

If you want to offer something other than what is specified, complete the bid as requested and then add additional sheets of paper describing your alternate offer.

It is critical that the bid be filled out and signed as required by the bid instructions in order to assure your bid is considered.


Bid Bond

Bid bonds are generally required on projects valued at $60,000 or more. Bid Bonds guarantee that the bidder on a project will enter into the contract and furnish the required payment and performance bonds. A bid bond is usually for 10% of the total project cost. The key here is that it must be included with the bid or your bid will be deemed non-responsive. Sometimes, depending on the job, we may require a bid bond for projects less than $60,000.

Performance and Payment Bonds

The successful bidder of projects valued at $60,000 or more must execute the required Performance and Payment Bonds within five (5) days after notice of award. The cost of the bonds must be including in the bid. The County includes the cost of bonding in the price evaluation.

  • Performance bond – the amount of bond to be given to secure faithful performance of the contract shall be equal to one hundred percent (100%) of the contract price thereof and shall provide, in effect that the principle shall sell and truly perform the "contract" rather than "work contracted to be done" as is quite common. If the latter language is used, the bond will be rejected.
  • Payment Bond – the amount of the bond to be given to secure the payment of all claims, demands, lien, or charges or material, men, mechanics or laborers employed by the contractor shall be equal to one hundred (100%) of the contract price.

Purchase Order vs. Contracts

Purchase Orders are normally issued for projects valued from $0.00 to $59,999. Sonoma County Construction Contracts are executed for projects valued at $60,000 or more. Remember to register to bid on the Supplier Portal.