Wyoming Building Codes, Permits and Contractor Rules
Here’s every rule from our 50-state guides for Wyoming on one page: the residential building code, frost depth, retaining wall permits, the 811 dig law, drainage law, contractor licensing, deposit limits, mechanics lien deadlines, workers’ comp, planting zones and frost dates. Each section links the official source and the full 50-state comparison.
Wyoming at a glance
- Building code: Set by cities and counties
- Frost depth: Set by your local building department
- 811 notice: At least 2 full business days, but not more than 14 business days, before excavation
- Contractors: No statewide requirement (local)
- Deposits: No statewide cap
- Liens: 150 days prime / 120 days sub
- Workers’ comp: Extra-hazardous jobs (state fund)
- Drainage rule: Unsettled
- Planting zones: 3b to 6a
| Topic | Wyoming | Compare |
|---|---|---|
| Residential building code | Set by cities and counties | All states |
| Frost line depth | Set by your local building department | All states |
| Retaining wall permit | Set locally | All states |
| 811 notice before digging | At least 2 full business days, but not more than 14 business days, before excavation | All states |
| Contractor license | No statewide requirement (local) | All states |
| Deposit limit | No statewide cap | All states |
| Right to cancel | 3 business days, credit sales at home | All states |
| Lien filing deadline | 150 days prime / 120 days sub | All states |
| Workers’ comp required | Extra-hazardous jobs (state fund) | All states |
| Drainage between neighbors | Unsettled | All states |
| Planting zones (2023 USDA) | 3b to 6a | All states |
| Frost dates (NOAA) | Last frost mid-May (Cheyenne) to late May (Casper); first frost late Sep (Casper) to early Oct (Cheyenne) | All states |
Wyoming residential building code
- Code
- No statewide residential code; cities and counties adopt their own (often a recent IRC)
- How it applies
- Local adoption (no statewide residential code)
- Code agency
- None for residential construction
- Who enforces it
- Cities and counties adopt and enforce their own codes; areas that have not adopted a code may have no building permits or inspections.
- Good to know
- Wyoming has no statewide house code. Your city or county sets the rules, and places that haven't adopted a code may not require building permits.
Compare building codes in all 50 states
Frost line depth in Wyoming
- Who sets it
- Local building department
- Local examples
- Town of Jackson: 34 in.
- Good to know
- For Cheyenne, Casper or other towns, check with the local building department.
Frost line depth in every state
Retaining wall permits in Wyoming
- Permit exemption
- Set locally
- Who decides
- Your city or county decides, if it has adopted a residential code.
- Good to know
- Some Wyoming cities and counties have adopted the IRC, but it isn't a statewide standard.
Retaining wall permit rules in every state
811 dig law in Wyoming
- One-call center
- One Call of Wyoming
- Notice before digging
- At least 2 full business days, but not more than 14 business days, before excavation
- Ticket good for
- 14 business days: the excavator must renew notice each succeeding 14-business-day period
- Hand-dig zone
- 24 in. horizontally from the exterior sides of the facility
- Homeowners
- Yes. 'Excavation' includes 'hand or power tools'; only tilling of soil and gardening or agricultural purposes are excluded. One Call of Wyoming: 'Any excavation project, NO MATTER HOW BIG OR HOW SMALL… requires all homeowners and excavators' to call.
- The law
- Wyo. Stat. Ann. §§ 37-12-301 to 37-12-307
- Good to know
- On longer jobs, renew your notice every 14 business days.
Drainage law and stormwater permits in Wyoming
- Rule
- We couldn’t confirm a settled rule here. Talk to a Wyoming attorney about a drainage dispute.
- What we found
- Not confirmed: the Wyoming Supreme Court opinion checked treats water reaching a neighbor's land as a negligence question (reasonable care in directing irrigation or waste water) without naming a surface-water doctrine.
- Leading case
- Reed v. Cloninger. Wyo. S. Ct. No. 05-74 (Mar. 24, 2006); citing Howell v. Big Horn Basin Colonization Co., 14 Wyo. 14, 81 P. 785 (1905)
- What it means for your yard
- Wyoming courts have treated damage from water directed onto a neighbor's land as a matter of reasonable care, but no clear rule for ordinary yard runoff was confirmed; talk to a Wyoming attorney about a dispute.
- Construction stormwater permit
- Wyoming Department of Environmental Quality (DEQ), Water Quality Division (WYPDES): 1 acre or more: Small Construction General Permit for 1 to under 5 acres (no application or NOI; follow permit provisions); Large Construction General Permit for 5 acres or more (NOI, SWPPP, fee and map)
- State rules below 1 acre
- No statewide rule below the 1-acre permit found; check your county and town.
- Local rules
- Wyoming cities and counties may have their own grading and drainage rules.
- Good to know
- We could not confirm a clear Wyoming rule for yard runoff between neighbors; the Wyoming Supreme Court has treated misdirected irrigation water as a reasonable-care question, so talk to a Wyoming attorney about a dispute. State construction stormwater coverage starts at 1 acre.
Contractor licensing in Wyoming
- Statewide rule
- No statewide requirement (local)
- Who needs it
- Wyoming does not appear to have a state general contractor license; electrical licensing is handled by the state Department of Fire Prevention and Electrical Safety.
- Licensed separately
- Electrical licenses (Department of Fire Prevention and Electrical Safety).
- Good to know
- Cities and counties may license contractors, so check with your local building department.
Contractor license requirements in every state
Contractor deposits and your right to cancel in Wyoming
- Deposit limit
- No statewide cap.
- Right to cancel
- Home solicitation sales on credit of $25 or more (personal or phone solicitation away from the seller's place of business): may cancel until midnight of the third business day after signing (Wyo. Stat. §§ 40-14-251, 40-14-252). For cash sales at your home, the federal 3-day Cooling-Off Rule applies.
- The law
- Wyo. Stat. §§ 40-14-251 to 40-14-256 (Uniform Consumer Credit Code, home solicitation sales)
- Good to know
- Wyoming's own 3-day cancel law covers credit sales made at your home; cash deals rely on the federal 3-day Cooling-Off Rule. Wyoming has no statewide general contractor license, so check references and any local licensing before paying.
Contractor deposit limits in every state
Mechanics lien deadlines in Wyoming
- Lien deadline (prime)
- File within 150 days after the earlier of last furnishing or substantial completion; the contract parties may extend by a recorded, notarized written agreement up to twice that period (Wyo. Stat. § 29-2-106).
- Lien deadline (sub/supplier)
- Within 120 days after the earlier of last furnishing or substantial completion (Wyo. Stat. § 29-2-106).
- Preliminary notice (sub/supplier)
- Required. Preliminary notice to the record owner within 30 days after first furnishing, with a copy to the contractor; missing it bars the lien (Wyo. Stat. § 29-2-112).
- Notice of intent
- Required: written notice of intent to the record owner (or agent) at least 20 days before filing the lien statement (Wyo. Stat. § 29-2-107).
- Enforce within
- Foreclosure action within 180 days after filing the lien statement (Wyo. Stat. § 29-2-109).
- The law
- Wyo. Stat. Title 29, Ch. 2 (Contractors or Materialmen), § 29-2-101 et seq.
- Good to know
- Wyoming requires everyone, including the prime contractor, to send the owner a preliminary notice (the prime before any payment, subs within 30 days), and a 20-day notice before filing a lien.
Mechanics lien deadlines in every state
Workers' comp requirements in Wyoming
- Who must carry it
- Employers in extra-hazardous industries must have coverage through the state fund (Department of Workforce Services) before work begins in Wyoming; industries are classed by NAICS code, and codes not listed as extra-hazardous are optional coverage (Wyoming DWS; Wyoming Legislative Service Office memo, June 2023). The statute lists construction (NAICS sector 23) and industry group 5617, services to buildings and dwellings, which includes landscaping services, as extra-hazardous (W.S. 27-14-108(a)(ii)(D), (M)); check your classification with DWS.
- Owners and officers
- Sole proprietors, partners, corporate officers and LLC members are not 'employees' unless coverage is elected (W.S. § 27-14-102(a)(vii), per ALFA International compendium).
- Subcontractors
- Not confirmed in an official source; confirm a sub's DWS coverage before work starts.
- Penalties
- No penalty amount published on an official source we could find. Ask the state agency.
- The law
- W.S. Title 27, Ch. 14 (Wyoming Worker's Compensation Act); §§ 27-14-102, 27-14-108
- State agency
- Wyoming Department of Workforce Services, Workers' Compensation Division
- Good to know
- Wyoming construction and landscaping businesses must buy coverage from the state fund before work starts; some other businesses can choose whether to cover. Owners, partners, officers and LLC members are excluded unless they elect coverage.
Workers' comp requirements in every state
Planting zones in Wyoming
- 2023 USDA zones
- 3b to 6a
- Coldest-night range
- −35°F to −5°F
- Example cities
- Cheyenne: 5b, Casper: 5a, Laramie: 4b, Jackson: 4b
- Good to know
- Most Wyoming towns fall in zones 4 and 5. Cheyenne is 5b, while high valleys such as Jackson and Laramie are 4b and the upper Green River basin is colder still.
Frost dates in Wyoming
| Station | Last spring frost | First fall frost | Frost-free days |
|---|---|---|---|
| Cheyenne Southeast Wyoming | May 12 | October 1 | 141 |
| Casper Central Wyoming | May 26 | September 22 | 117 |
| Sheridan North-central Wyoming | May 21 | September 23 | 123 |
| Rock Springs Southwest Wyoming | May 22 | September 28 | 126 |
- Typical range
- Last frost mid-May (Cheyenne) to late May (Casper); first frost late Sep (Casper) to early Oct (Cheyenne)
- Good to know
- These are typical (50%) dates from NOAA's 1991–2020 climate normals, so about half of years still bring a 32°F night after the listed spring date. In Wyoming, the last spring frost at the stations listed ranges from mid-May around Cheyenne to late May around Casper.
- Local frost or planting guide
- University of Wyoming Extension
Frequently Asked Questions
What building code does Wyoming use?
No statewide residential code; cities and counties adopt their own (often a recent IRC). It applies as follows: local adoption (no statewide residential code). Your local building department can confirm the edition and amendments for your address.
How deep is the frost line in Wyoming?
Frost depth is set by local building departments. Footings for houses, additions and attached decks go below it.
How much can a contractor ask for up front in Wyoming?
No statewide cap. Cancel rights: Home solicitation sales on credit of $25 or more (personal or phone solicitation away from the seller’s place of business): may cancel until midnight of the third business day after signing (Wyo. Stat. §§ 40-14-251, 40-14-252). For cash sales at your home, the federal 3-day Cooling-Off Rule applies.
How long does a contractor have to file a mechanics lien in Wyoming?
File within 150 days after the earlier of last furnishing or substantial completion; the contract parties may extend by a recorded, notarized written agreement up to twice that period (Wyo. Stat. § 29-2-106). Subcontractors and suppliers may have different notice rules; see the section above.
What planting zone is Wyoming?
On the 2023 USDA map, Wyoming runs from zone 3b to 6a. Examples: Cheyenne 5b, Casper 5a, Laramie 4b. Enter your ZIP on the USDA map for your exact zone.
Do contractors need workers' comp in Wyoming?
Employers in extra-hazardous industries must have coverage through the state fund (Department of Workforce Services) before work begins in Wyoming; industries are classed by NAICS code, and codes not listed as extra-hazardous are optional coverage (Wyoming DWS; Wyoming Legislative Service Office memo, June 2023). The statute lists construction (NAICS sector 23) and industry group 5617, services to buildings and dwellings, which includes landscaping services, as extra-hazardous (W.S. 27-14-108(a)(ii)(D), (M)); check your classification with DWS. Owner exemptions and subcontractor rules are in the workers’ comp section above.
When is the last frost in Wyoming?
At the NOAA stations we list: Last frost mid-May (Cheyenne) to late May (Casper); first frost late Sep (Casper) to early Oct (Cheyenne). These are typical (50%) dates from the 1991–2020 climate normals, so about half of years still bring a 32°F night after the spring date.
This page is general information, not legal or tax advice. Rules change; the agencies and statutes linked above have the final word.
Wyoming in each 50-state guide: Frost line depth · 811 dig laws · Retaining wall permits · Contractor licensing · Contractor deposit limits · Building codes · Planting zones · Mechanics lien deadlines · Workers' comp · Frost dates · Drainage laws · Noxious weed laws · Rainfall and snowfall · Landscaper pay · Pesticide applicator licensing · Landscaping sales tax · All state guides
Last checked October 31 and November 1, 2026 against official state and local sources for this state. Rules change; your state agency or local building department has the final word. Spot something out of date? Email info@muthlerlandscaping.com and we’ll fix it.
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Cite as: Muthler Landscaping & Construction, “Wyoming Building Codes, Permits and Contractor Rules,” https://muthlerlandscaping.com/state-guides/wyoming/ (last checked November 9, 2026).
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