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Tree Permits in San Mateo County (unincorporated)

San Mateo County (unincorporated) requires a permit to remove any species at 12.1″; indigenous species at 10″; douglas fir or coast redwood at 18″; 4 more protected classes. Measured as trunk diameter (DBH) at 54″ above grade. Arborist report required with the application. Permit fee from $444. Verified October 12, 2026.

Check my treeArborist report for San Mateo County (unincorporated)

Last verified · fees checked · Michael Schuck, ISA Certified Arborist WE-15750A, Certified Urban Forest Professional WE-15750AF

San Mateo County (unincorporated) tree ordinance at a glance

Code sectionSan Mateo County Ordinance Code Title 8, Art. 7, Ch. 8.400 Protected Tree Ordinance, secs. 8.400.010-8.400.290 (Ord. 4895, adopted 10/22/2024), which rescinded and replaced the former Ch. 8.400 Significant Tree Regulations (Sec. 12,000 et seq.) and Ch. 8.404 Heritage Tree Regulations (Sec. 11,000 et seq., 1977)
Protected treesProtected trees (8.400.060): (1) ANY species 12.1" diameter (38" circumference) or larger at 4.5 ft; (2) Protected Indigenous Trees per Table 1 at lower sizes: bigleaf maple, box elder, Pacific madrone, California buckeye, golden chinquapin, Oregon ash, Santa Cruz cypress, California sycamore, coast live oak, canyon live oak, blue oak, Shreve oak, black oak, valley oak, interior live oak and California nutmeg at 10"; Douglas fir and coast redwood at 18"; white/red alder and Fremont cottonwood 6" within riparian corridors; willows any size in riparian corridors and 6" trunks outside; Oregon white oak any size; (3) Board-designated Heritage Trees; (4) replacement trees and trees retained by a permit/development condition or enforcement action; (5) a 'community of trees' (five or more same-species indigenous trees over 6" DSH on one parcel, or an ecologically related group); (6) carbon-sequestration/mitigation trees. In the Emerald Lake Hills, Oak Knoll Manor, Palomar Park and Devonshire design review districts ANY tree 6" diameter (19" circumference) or larger is protected (8.400.070). RM and TPZ (and RM/CZ, PAD, TPZ/CZ outside the Midcoast urban area) parcels outside scenic corridors need no permit under this chapter (8.400.080-.090). Pruning permits: cuts 6" or larger on indigenous trees, any oak 30" DSH+ in urban areas, any heritage tree.
Size threshold12.1" DSH / 38" circumference (any species); indigenous species 10" (most), 18" (redwood, Douglas fir), 6" (riparian alder/cottonwood/willow), any size (Oregon white oak); 6" DSH / 19" circumference in Emerald Lake Hills, Oak Knoll Manor, Palomar Park and Devonshire DR districts; all at 4.5 ft (54")
Ordinance states both units: '12.1 inches in diameter (38 inches circumference) or larger when measured 4.5 feet (54 inches) above natural grade'. The County web page rounds this to '12 inches or more in diameter' and '6 inches or more in the Residential Hillside (RH) District'. Coastal Zone caveat: the 2024 ordinance takes effect there only on Coastal Commission certification (conditionally certified 8/12/2026 per the County project page); until final, the former Significant Tree Regulations (38" circumference at 4.5 ft) govern Coastal Zone parcels.
Multi-trunk trees8.400.030(12): 'Measurement of multi-trunk trees is determined by adding the largest stem diameter to one-half of the next two largest stem diameters, measured at 4.5 feet (54 inches) above natural grade.' A multi-trunk tree has more than one major stem from a single root mass at ground level or just above the trunk flare, excluding suckers and root sprouts (8.400.030(20)).
Dead or hazardous treesDEAD trees need no permit (8.400.100(8)); 'dead tree' = no longer alive or in advanced decline with less than 10% natural vigor 'as determined by a Certified or Consulting Arborist; or can otherwise be shown to be dead as determined by the Director of Planning and Building' (8.400.030(8)); County page: notifying Planning staff first is 'highly recommended'. EMERGENCY (8.400.230): a protected tree may be removed or severely pruned without a prior permit where it 'presents an imminent danger to life, property, utilities, or essential transportation systems, or a tree risk rating of High or Extreme is present, as assessed by an ISA Tree Risk Assessment Qualified Arborist (TRAQ)'; the owner must notify the Director (or the Sheriff after hours), photograph the tree, and within 72 hours submit photos and a TRAQ arborist's written verification; replacement trees are required; otherwise it is treated as a violation. Emergency Tree Removal Permit fee $221. FIRE-RISK SPECIES exemption (8.400.100(4)): eucalyptus, pines, acacia, tanoak and bay laurel with the trunk within 100 ft of any habitable structure (including neighbours') or 30 ft of an evacuation road need no permit unless 38" DSH or larger; defensible-space removals identified by CAL FIRE, the County Fire Marshal or local fire authority in High/Very High fire hazard zones are also exempt ((5)). Separate annual Director notice 'Permit Exemption for Hazardous Trees - Extended to July 1, 2027' (dated July 1, 2026) waives permits and fees for the same five species within 100 ft of a habitable structure or 30 ft of an emergency-evacuation road; the page is headed 'Only applicable to the Coastal Zone' (where the old Significant Tree Regulations still apply). Hazard trees not meeting the emergency test go through the normal permit with an arborist report; High/Extreme ratings need a TRAQ arborist's ISA Basic Tree Risk Assessment Form.
Permit fee (FY 2026-27)Planning Service Fee Schedule (updated 07/09/2026; Res. 080751 effective April 1, 2026, amended by Res. 082009 adopted June 23, 2026, effective July 23, 2026), 'Tree Permits': Protected Tree Removal Permit $444 per tree; Protected Tree Pruning Permit $331 per tree; Expedited Tree Removal Permit $221 per tree; Emergency Tree Removal Permit $221; Heritage Tree - New Designation $3,883; Appeal of Any Permit $2,021; violation fees charged at ten times the amount for tree cutting/trimming violations. In-lieu replacement fee $3,345 per tree not replaced on site (8.400.160(3)). CONFLICT: the County's Tree Trimming and Removal Permit web page still states 'Approximate Fee: Protected Tree (Removal: $670 / Pruning: $550), Expedited Removal: $430' (undated); the adopted schedule governs. Other department review fees (geotechnical, Public Works, Environmental Health, fire) may apply. fee schedule
Penalties for removal without a permitTable 3 (8.400.260) fines per tree by cumulative inches of DSH removed: first violation $1,500 (12-24" DSH) / $4,500 (25-48") / $7,500 (over 48"); second violation $4,500 / $10,500 / $18,000; third $7,500 / $15,000 / $22,500; served on the record owner and may also be served on the person doing the work; each tree is a separate infraction. Plus cease-work order, mitigation plan with new arborist report and replacement at the Director's discretion, stop-work on development until mitigation is installed and fees paid, a development moratorium of up to 18 months for violations outside development, a non-revocable maintenance bond, and a recorded notice of violation (8.400.250-.280). Fee schedule: violation permit fees at ten times the normal amount.
Arborist reportRequired. Every Protected Tree Removal Permit and Protected Tree Pruning Permit application (8.400.120(2): 'An arborist report, consistent with this ordinance and its companion document'); the County application form (updated 04/21/2026) says 'Please refer to the Arborist Report Template for guidance on preparing a complete report' and sanmateocountytrees.org: 'Reports are required with a protected tree removal or protected tree pruning permit application'. NOT required for an Expedited Tree Removal Permit for the listed species (acacia, fruit/nut trees, tree of heaven, Italian cypress, eucalyptus, Monterey cypress outside the Coastal Zone, privet, sweetgum, tanoak, magnolia, myoporum, olive, pines, ornamental pear, pepper tree, bay laurel, palms except Canary Island date palm; max 3 trees per parcel per year), which needs photos only (8.400.130(2)). Emergency removals need a TRAQ arborist's written verification within 72 hours (8.400.230(2)). Dead-tree exemption rests on a certified/consulting arborist's determination (8.400.030(8)). Development applications need an Existing Tree Plan and Tree Protection Plan prepared by a certified arborist (8.400.170). The 8.400.120 list also allows the Director to require a licensed architect/engineer report where structural damage is claimed.
Who may write it: 'CERTIFIED OR CONSULTING ARBORIST' (8.400.030(5)): certified by the International Society of Arboriculture, a member of the American Society of Consulting Arborists, or an arboricultural professional approved by the Director of Planning and Building; 'ARBORIST REPORT means a professional report prepared by a certified arborist that meets the requirements outlined in the companion website' (8.400.030(1)). Hazard/emergency ratings must come from a Tree Risk Assessment Qualified (TRAQ) arborist.
Who to callSan Mateo County Planning and Building Department, Current Planning Section, 455 County Center, 2nd Floor (Mail Drop PLN 122), Redwood City 94063; (650) 363-4161 (fee schedule and application form); Planning Desk (650) 363-1825; planningprojects@smcgov.org (applications may be emailed); online via Accela https://aca-prod.accela.com/smcgov; companion site https://sanmateocountytrees.org/ · official page
Recent changes
  • : Fee schedule updated (FY 2026-27): Planning Service Fee Schedule (updated 07/09/2026; Res. 080751 effective April 1, 2026, amended by Res. 082009 adopted June 23, 2026, effective July 23, 2026), 'Tree…

Sources: smcgov.org · sanmateocountytrees.org. Urban Forestry Guide is not a city line; for San Mateo County (unincorporated) permit questions use the department above.

Does my tree need a permit in San Mateo County (unincorporated)?

A permit is required when the tree is protected and meets the size rule. San Mateo County (unincorporated) measures trunk diameter (DBH) at 54″ above the ground.

Unincorporated County only (Emerald Hills, North Fair Oaks, West Menlo Park, Ladera, Highlands, Midcoast, etc.); the County page still quotes $670 removal / $550 pruning / $430 expedited while the adopted FY 2026-27 schedule lists $444 / $331 / $221 per tree.

An arborist report (County template) is required with every Protected Tree Removal or Pruning permit; expedited-list species need photos only. 300-ft mailed notice, 10-day posting with yellow caution tape, decision in roughly 1-2 months, 10-business-day appeal.

RM and TPZ parcels outside scenic corridors need no permit under this chapter (8.400.080-.090).

Coastal Zone effective date of Ch. 8.400 (Coastal Commission conditional certification 8/12/2026).

County web-page fees vs adopted schedule.

Check my tree in the permit checker

Street trees, city-designated heritage trees and trees required by a development approval are protected at any size in every city. Trees on lot lines belong to both owners.

Does San Mateo County (unincorporated) require an arborist report?

Yes. Every Protected Tree Removal Permit and Protected Tree Pruning Permit application (8.400.120(2): 'An arborist report, consistent with this ordinance and its companion document'); the County application form (updated 04/21/2026) says 'Please refer to the Arborist Report Template for guidance on preparing a complete report' and sanmateocountytrees.org: 'Reports are required with a protected tree removal or protected tree pruning permit application'. NOT required for an Expedited Tree Removal Permit for the listed species (acacia, fruit/nut trees, tree of heaven, Italian cypress, eucalyptus, Monterey cypress outside the Coastal Zone, privet, sweetgum, tanoak, magnolia, myoporum, olive, pines, ornamental pear, pepper tree, bay laurel, palms except Canary Island date palm; max 3 trees per parcel per year), which needs photos only (8.400.130(2)). Emergency removals need a TRAQ arborist's written verification within 72 hours (8.400.230(2)). Dead-tree exemption rests on a certified/consulting arborist's determination (8.400.030(8)). Development applications need an Existing Tree Plan and Tree Protection Plan prepared by a certified arborist (8.400.170). The 8.400.120 list also allows the Director to require a licensed architect/engineer report where structural damage is claimed.

Who may write it: 'CERTIFIED OR CONSULTING ARBORIST' (8.400.030(5)): certified by the International Society of Arboriculture, a member of the American Society of Consulting Arborists, or an arboricultural professional approved by the Director of Planning and Building; 'ARBORIST REPORT means a professional report prepared by a certified arborist that meets the requirements outlined in the companion website' (8.400.030(1)). Hazard/emergency ratings must come from a Tree Risk Assessment Qualified (TRAQ) arborist.. None. County publishes an Arborist Report Template (sanmateocountytrees.org, County-of-San-Mateo-Arborist-Report-Template_2024.docx) and links the ISA and ASCA directories.

“Applications for Protected Tree Removal or Protected Tree Pruning permits shall include the following: 1. A completed tree removal or tree pruning application form provided by the Planning Department, signed by the property owner. 2. An arborist report, consistent with this ordinance and its companion document.” municipal code
Need a report San Mateo County (unincorporated) will accept? Michael Schuck writes ISA Certified Arborist reports for permit applications, hazard claims and disputes across the Bay Area, including San Mateo County (unincorporated).
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How to get a tree removal permit in San Mateo County (unincorporated)

  1. Check whether a permit is needed with the County's 'Do I Need a Tree Permit?' survey (sanmateocountytrees.org/doineedapermit) or the Planning Desk (650) 363-1825: any tree 12.1 inches DSH (38 inches circumference) or larger, indigenous species at the Table 1 sizes, any tree 6 inches DSH or larger in the Emerald Lake Hills/Oak Knoll Manor, Palomar Park and Devonshire design review districts, heritage trees, replacement/condition trees and communities of trees are protected; dead trees, fire-risk species near structures and roads, defensible-space work and emergencies are exempt (8.400.060-8.400.100). Coastal Zone parcels may also need a Coastal Development Permit. source
  2. Expedited route for the 8.400.130 species list (acacia, fruit/nut, tree of heaven, Italian cypress, eucalyptus, Monterey cypress outside the Coastal Zone, privet, sweetgum, tanoak, magnolia, myoporum, olive, pines, flowering pear, pepper tree, bay laurel, most palms), up to three trees per parcel per year: application form signed by the owner, photos adequate to show species and size, $221 per tree; the Director acts without public notice or hearing; replacement planting from the County species list is a condition; not appealable. source
  3. Standard route: file the 'Permit to Remove/Prune Tree(s) Application' (updated 04/21/2026) by email to Planningprojects@smcgov.org or through the Accela portal with: an arborist report (County template recommended) stating the 8.400.150 findings, photographs of each tree from several aspects, a site sketch by parcel quadrant with driplines, a replanting plan with species, size and GPS coordinates, any Existing Tree Plan/Tree Protection Plan for development, an architect/engineer report if structural damage is claimed, and the fee ($444 per tree removal; $331 per tree pruning) (8.400.120). source
  4. Notice: the Director mails notice to owners within 300 feet (and the Midcoast Community Council for Midcoast sites); the applicant posts the County notice form in two conspicuous roadside locations for at least 10 calendar days and wraps each tree proposed for removal in yellow caution tape during the posting period (8.400.140(1)). source
  5. Staff review and site inspection; the Director approves, conditionally approves or denies on the written findings of 8.400.150 (without development: two or more of: Migratory Bird Treaty Act compliance; severe decline/disease per the arborist report; hazard tree or public nuisance; suppression of a higher-value protected tree; infrastructure damage with no reasonable fix; utility interference; geologic-hazard repair), issuing a written statement of action, conditions and findings (8.400.140(5)); County page: approximately 1-2 months. source
  6. After the 10-business-day appeal period, post the approved permit at eye level nearest the street during the work (8.400.210), remove the tree within one year or the permit is void (8.400.190), and plant replacement trees per Table 2 within one year (application form), maintaining them for three years (8.400.160); pay $3,345 per tree in lieu where replanting is inappropriate. source
TimelineCounty page: 'Approximate Time: 1-2 Months' (excluding appeals). Code: applicant posting at least 10 calendar days; 300-ft mailed notice; appeal within 10 business days of issuance or denial, Planning Commission decision within 15 calendar days of its hearing; permit void if work not commenced within 1 year (8.400.190); replacement planting within 1 year and 3-year maintenance; emergency documentation within 72 hours.
“Approximate Time: 1-2 Months” source
AppealThe applicant or any aggrieved person may appeal a Protected Tree Removal or Pruning decision to the Planning Commission by written notice filed with the Department and payment of the appeal fee ($2,021 'Appeal of Any Permit') within 10 business days of issuance or denial; the Commission decides within 15 calendar days of its hearing; a further appeal to the Board of Supervisors within 10 business days, decided within 15 days of hearing, is final. Expedited Tree Removal Permits and Protected Tree Pruning Permits may not be appealed (8.400.200). Application form: authority to remove is effective only after the appeal period has expired.
“The permit decision by the Director of Planning and Building may be appealed to the Planning Commission by filing a written notice of appeal with the Department and paying an appeal fee as set by the Board of Supervisors within ten (10) business days of the issuance or denial of the subject permit.” source
Replacement8.400.160 Table 2 by canopy of the removed tree: up to 25 ft canopy = one 15-gallon tree (one 24-inch box with development); 25-40 ft = two 15-gallon (two 24-inch box with development); more than 40 ft = three 24-inch box or two 36-inch box (same with development). Species from the County's Protected Tree Replacement Species List; removed indigenous trees replaced with the same species unless the Director decides otherwise; expedited-list species may not be planted as replacements; three-year maintenance (reset if a replacement dies); planting may be postponed up to 9 months; in-lieu fee $3,345 per tree to the County Tree Replacement Fund where replanting is inappropriate. Expedited permits: one or more replacement trees from the County list unless inappropriate. source
FormsPermit to Remove/Prune Tree(s) Application (Chapter 8.400; updated 04/21/2026) · Tree Trimming and Removal Permit page (Planning and Building) · Ordinance 4895 - Chapter 8.400 Protected Tree Ordinance (adopted ordinance text) · Planning Service Fee Schedule (updated 07/09/2026; effective July 23, 2026) · Permit Exemption for Hazardous Trees - Extended to July 1, 2027 (Director notice, July 1, 2026) · sanmateocountytrees.org companion site (permit requirements, 'Do I Need a Tree Permit?', Arborist Report Template, species lists)

Process verified October 12, 2026 against the city's code, forms and department pages.

Frequently asked questions about tree permits in San Mateo County (unincorporated)

Do I need a permit to remove a dead tree in San Mateo County (unincorporated)?

DEAD trees need no permit (8.400.100(8)); 'dead tree' = no longer alive or in advanced decline with less than 10% natural vigor 'as determined by a Certified or Consulting Arborist; or can otherwise be shown to be dead as determined by the Director of Planning and Building' (8.400.030(8)); County page: notifying Planning staff first is 'highly recommended'. EMERGENCY (8.400.230): a protected tree may be removed or severely pruned without a prior permit where it 'presents an imminent danger to life, property, utilities, or essential transportation systems, or a tree risk rating of High or Extreme is present, as assessed by an ISA Tree Risk Assessment Qualified Arborist (TRAQ)'; the owner must notify the Director (or the Sheriff after hours), photograph the tree, and within 72 hours submit photos and a TRAQ arborist's written verification; replacement trees are required; otherwise it is treated as a violation. Emergency Tree Removal Permit fee $221. FIRE-RISK SPECIES exemption (8.400.100(4)): eucalyptus, pines, acacia, tanoak and bay laurel with the trunk within 100 ft of any habitable structure (including neighbours') or 30 ft of an evacuation road need no permit unless 38" DSH or larger; defensible-space removals identified by CAL FIRE, the County Fire Marshal or local fire authority in High/Very High fire hazard zones are also exempt ((5)). Separate annual Director notice 'Permit Exemption for Hazardous Trees - Extended to July 1, 2027' (dated July 1, 2026) waives permits and fees for the same five species within 100 ft of a habitable structure or 30 ft of an emergency-evacuation road; the page is headed 'Only applicable to the Coastal Zone' (where the old Significant Tree Regulations still apply). Hazard trees not meeting the emergency test go through the normal permit with an arborist report; High/Extreme ratings need a TRAQ arborist's ISA Basic Tree Risk Assessment Form.

What is the fine for removing a tree without a permit in San Mateo County (unincorporated)?

Table 3 (8.400.260) fines per tree by cumulative inches of DSH removed: first violation $1,500 (12-24" DSH) / $4,500 (25-48") / $7,500 (over 48"); second violation $4,500 / $10,500 / $18,000; third $7,500 / $15,000 / $22,500; served on the record owner and may also be served on the person doing the work; each tree is a separate infraction. Plus cease-work order, mitigation plan with new arborist report and replacement at the Director's discretion, stop-work on development until mitigation is installed and fees paid, a development moratorium of up to 18 months for violations outside development, a non-revocable maintenance bond, and a recorded notice of violation (8.400.250-.280). Fee schedule: violation permit fees at ten times the normal amount.

How long does a tree removal permit take in San Mateo County (unincorporated)?

County page: 'Approximate Time: 1-2 Months' (excluding appeals). Code: applicant posting at least 10 calendar days; 300-ft mailed notice; appeal within 10 business days of issuance or denial, Planning Commission decision within 15 calendar days of its hearing; permit void if work not commenced within 1 year (8.400.190); replacement planting within 1 year and 3-year maintenance; emergency documentation within 72 hours.

Does San Mateo County (unincorporated) require an arborist report for a tree removal permit?

Required. Every Protected Tree Removal Permit and Protected Tree Pruning Permit application (8.400.120(2): 'An arborist report, consistent with this ordinance and its companion document'); the County application form (updated 04/21/2026) says 'Please refer to the Arborist Report Template for guidance on preparing a complete report' and sanmateocountytrees.org: 'Reports are required with a protected tree removal or protected tree pruning permit application'. NOT required for an Expedited Tree Removal Permit for the listed species (acacia, fruit/nut trees, tree of heaven, Italian cypress, eucalyptus, Monterey cypress outside the Coastal Zone, privet, sweetgum, tanoak, magnolia, myoporum, olive, pines, ornamental pear, pepper tree, bay laurel, palms except Canary Island date palm; max 3 trees per parcel per year), which needs photos only (8.400.130(2)). Emergency removals need a TRAQ arborist's written verification within 72 hours (8.400.230(2)). Dead-tree exemption rests on a certified/consulting arborist's determination (8.400.030(8)). Development applications need an Existing Tree Plan and Tree Protection Plan prepared by a certified arborist (8.400.170). The 8.400.120 list also allows the Director to require a licensed architect/engineer report where structural damage is claimed.

How does San Mateo County (unincorporated) measure a tree for the permit threshold?

Trunk diameter (DBH) at 54 inches above grade. Diameter at 4.5 ft (54") above natural grade (DSH): any species 12.1" (38" circumference); most indigenous species 10"; redwood and Douglas fir 18"; 6" in the four Bayside design review districts.

Tree permits in nearby cities

Atherton · Belmont · Burlingame · East Palo Alto · Foster City · Hillsborough · Menlo Park · Pacifica

Compare all 45 cities in the 45-city ordinance table, or run the permit checker.

Not sure what San Mateo County (unincorporated) will ask for?

A 20-minute call with an ISA Certified Arborist usually settles it: permit or no permit, report or no report, and what it will cost.

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