How to sell to South Dakota counties

South Dakota has 66 counties. Counties buy under the state procurement code, SDCL chapter 5-18A, which applies to every "purchasing agency," meaning any governmental body authorized to contract (SDCL 5-18A-1). The same bid limits apply to counties, cities and school districts. Construction rules are in SDCL chapter 5-18B and bonds in chapter 5-21. The state Department of Legislative Audit publishes a plain-language guide to these rules, the Bid Booklet (July 1, 2024 edition).

At a glance

Who buys

Each county is governed by an elected Board of County Commissioners, which manages county fiscal affairs and property (SDCL 7-8-20) and awards contracts. State law does not create a county purchasing officer. In practice the county auditor usually publishes bid notices and handles bid openings, but check each county.

Goods and services

Professional services are not covered by the $50,000 advertising rule (SDCL 5-18A-14). Purchases can't be split to stay under the limit (SDCL 5-18A-11). According to the Bid Booklet, annual purchases of the same kind of item, installment totals and trade-in deals count at their gross value toward the limit.

A county may use competitive sealed proposals (an RFP) after a written finding that sealed bidding is not practicable or advantageous. Award goes to the most advantageous offeror on the stated factors (SDCL 5-18A-6, 5-18A-7). Reverse auctions are allowed for supplies and nonprofessional services (SDCL 5-18A-39, 5-18A-40).

Construction and public works

Public improvements of $100,000 or more must be advertised and bid (SDCL 5-18A-14). Plans and specifications must be on file, and one free copy goes to each South Dakota resident bidder acting in good faith (SDCL 5-18B-1). Design-build (SDCL 5-18B-20 to -38) and construction manager at risk (SDCL 5-18B-39 to -44) are also authorized, per the Bid Booklet.

Bid security. A certified or cashier's check for 5% of the bid, or a bid bond for 10%. The county may waive it when the bid is $100,000 or less (SDCL 5-18B-2, 5-18B-3, 5-18A-35, per the Bid Booklet).

Bonds. A performance bond for 100% of the contract price, which also covers payment for labor and materials. It may be waived when the bid is $100,000 or less, or in an emergency (SDCL 5-21-1, 5-21-1.1, 5-21-1.3, 5-18A-36).

Highway work. Since July 1, 2026, DOT highway construction contracts, and a political subdivision's utility work bid together with a DOT highway contract, are exempt from the code (SDCL 5-18A-22(1)-(2), as amended by SB 26).

Notice and award

Bid notices run as a legal notice at least twice (SDCL 5-18A-14):

• The first runs at least 10 days before the opening in each of the county's official newspapers.
• The second may run in any legal newspaper in the state.
• The notice gives the time and place of opening and reserves the right to reject any or all bids.

State law does not require website posting. Agencies may use the state's optional central bid exchange (SDCL 5-18A-13, per the Bid Booklet).

Award goes by written notice to the lowest responsible bidder with a responsive bid: within 30 days of opening for services and public improvements, and within 45 days for supplies. Tie bids are settled by lot or rebid (SDCL 5-18A-5, per the Bid Booklet).

Prevailing wage

South Dakota has no state prevailing wage law (US Department of Labor, state prevailing wage laws page). Federal Davis-Bacon rates can still apply when a county project uses federal funds; check the solicitation.

Getting paid

Prompt payment. The prompt payment law expressly covers counties (SDCL 5-26-1). A county must pay by the date in the contract or, if none, within 45 days after it receives and accepts the goods or services and the invoice (SDCL 5-26-2). Late payments earn interest at the Category B rate (SDCL 54-3-16) or the contract rate, accruing from the 30th day. Interest under $5 need not be paid (SDCL 5-26-3, 5-26-3.1).

Retainage. On public improvements, the agency makes progress payments for completed work and may withhold what is needed to finish until acceptance (SDCL 5-18B-11, per the Bid Booklet). For county public buildings, Levelset's summary of SDCL 7-25-10 lists retainage of 12% of the first $50,000, 5% of the next $200,000 and 2.5% above $250,000, with retainage and final payment due 60 days after completion and interest after that. We did not read the official text of 7-25-10; check the contract.

Cooperative purchasing and state contracts

Cooperative purchasing is exempt from bidding for supplies and nonprofessional services bought from an active contract that any government entity awarded by competitive sealed bids or proposals, or competitively solicited and awarded in the prior 12 months (SDCL 5-18A-22(4), numbered (3) before July 1, 2026). Also exempt (SDCL 5-18A-22):

• Purchases through GSA or other federal contracts.
• Midwestern Higher Education Compact contracts.
• Communications technology and computer hardware and software.

Counties may also buy from the lowest bidder on the state price list (SDCL 5-18C-8, per the Bid Booklet). A June 25, 2026 Attorney General opinion, written for school districts, says cooperative contracts can't be used for public improvements of $100,000 or more (AG Op. 26-03, secondary: ezel.ai summary).

Preferences and required certifications

• Tie bids: resident businesses and South Dakota manufacturers get preference on tie bids (SDCL 5-18A-25 to -27, per the Bid Booklet).
• Reciprocal preference: applied against bidders from states that favor their own residents, using a state-maintained list (SDCL 5-18A-25 to -27).
• No price preference: the Bid Booklet found no general local or veteran price preference.
• Prohibited foreign entities: agencies may not contract with entities tied to China, Cuba, Iran, North Korea, Russia or Venezuela. Bidders certify, and a false certification is grounds for debarment (SDCL 5-18A-50 to -53, per the Bid Booklet).

Statewide county rules on E-Verify and boycott certifications were not confirmed; check the solicitation.

Architects and engineers

A political subdivision's contracts for architectural and engineering services are exempt from the procurement code (SDCL 5-18A-22(17)). We found no county qualifications-based selection mandate, so each county sets its own process. On public improvements over $100,000, the same firm can't be both the architect or engineer and the contractor or construction manager (SDCL 5-18B-15, per the Bid Booklet).

Recent changes

• 2023: HB 1060 (SL 2023, ch 17, signed Feb. 22, 2023) raised the advertised bid limit for supplies and services from $25,000 to $50,000 (SDCL 5-18A-14).
• July 1, 2026: SB 26 (SL 2026, ch 29) added the DOT highway exemptions and renumbered SDCL 5-18A-22; the cooperative purchasing exemption is now 5-18A-22(4).
• June 25, 2026: AG Op. 26-03 said cooperative contracts can't replace bidding for public improvements of $100,000 or more (secondary summary).

Practical tips for South Dakota

• Watch each county's official newspapers. Legal notices may run just 10 days before the opening.
• Ask for the county's purchasing procedures under $50,000. State law leaves quotes to each county.
• Offer your cooperative contract for supplies and services. A competitively awarded government contract lets a county skip its own bid (SDCL 5-18A-22(4)).
• Have bid security ready on public improvements: 5% by check or a 10% bid bond.
• Check South Dakota counties for each county's bid platform, contacts and agendas.