Approved contractor and credential-check schemes for tree work

The United Kingdom's Arboricultural Association says plainly that tree work is not directly regulated, and it is possible to set up a company and claim to offer a service even if those involved do not have the necessary credentials. The schemes below fill that gap on a voluntary basis. Some assess a business. Some list individuals. This page describes each scheme as its own pages do. It does not name any business that holds one, and it does not rank the schemes. For credentials held by individuals, read ISA credentials and certifications by country.

Two kinds of scheme

Kind	What is checked	Examples below
Business scheme	Systems, safety, insurance, staff and sample work	TCIA, ARB Approved Contractor, QAA, NZ Arb
Person credential	One individual's exam, experience or membership	ISA, ASCA, Registered Consultant, Arb Aus registered

The difference matters when you read an advert. ISA states on its false advertisements page that ISA credentials are earned by individuals, never by a company. Its rules for advertising say an ad for a credential holder must list the person's name and ISA certification ID number.

United States

TCIA Accreditation

The Tree Care Industry Association describes TCIA Accreditation as a third-party consumer confidence verification program for tree care companies. It says accreditation helps consumers identify qualified companies who conduct business in a safe, legal and ethical manner. The program is voluntary. TCIA's page for people hiring a tree care company calls it a voluntary program that credentials companies meeting criteria for professionalism, employee training, state and federal safety regulations, business ethics and customer satisfaction.

Who can apply. The main page says any commercial tree care company in the United States and Canada can apply. The FAQ page adds the United Kingdom and says members of TCIA save money on enrolment.
How long it lasts. Certification is in effect for three years, with a renewal check-up required every year. The yearly check-ups confirm that the company has the required number of arborists on staff, is properly insured, and has a good safety and customer satisfaction rating.
Each site counts. The FAQ says a company with more than one location must have each facility accredited and its employees trained.
Independence. The FAQ says an auditor who consults with a company cannot audit it.
Checking a company. TCIA says its website has an accredited company search for consumers. It also publishes an accreditation logo violators page, which lists companies it says falsely claim to be accredited.

TCIA's own application form, marked active for September 2026 to August 2027, shows a flat enrolment fee per facility of US$1,113 for TCIA members and US$2,226 for non-members. It shows an annual renewal fee of US$998 for members and US$1,996 for non-members. The form says the flat fee covers the auditor's site visit travel costs. TCIA's overdue audit policy adds a late fee of US$100 per month when a yearly audit is done after the required calendar year.

TCIA also runs a separate Utility Contractor Accreditation. It describes this as a business practices and compliance-audit process for commercial right-of-way vegetation management and utility line clearance contractors. The standards it lists include ANSI A300 and ANSI Z133. For the rules behind that work, read utility line clearance.

TCIA's hiring page also tells readers to see whether their municipality requires licensing for arborists, since many communities do. Accreditation is not a license. For license rules, read state arborist licenses.

ISA credentials and Find an Arborist

ISA certification is for people, not businesses. The ISA Certified Arborist program guide says ISA certifications do not represent licensure, registration or other authorization to practice or to conduct business activities. It says Certified Arborist certification is valid for three years, and that one route to recertify is at least 30 continuing education units over the three-year period plus a fee.

The public search is the Find an Arborist page. It says the platform is designed to help the public, employers and industry stakeholders find and check ISA-credentialed tree care professionals. Three points from that page and the program guide matter when you read a result.

Listings are voluntary. The page says the listing is available to credential holders via their digital badge and that some users choose to remove themselves from it.
The program guide says a holder's name, ISA credentials and digital certificates are available to the public on the ISA Spotlight Directory unless the holder makes them private. It also says ISA keeps the right and responsibility to verify a credential holder's certification status to the public or other interested parties.
ISA says certification shows the minimum knowledge and skill needed for the scope of the program the person holds. It promotes hiring companies that have ISA certified professionals on staff, which is a statement about staff, not a company credential.

In Canada, the ISA Ontario hiring page points people to the same site to check certification by name or certification number. It tells hirers to confirm that a company has the right credentials, liability insurance and WSIB documents. An ISA Ontario notice says holders who earlier opted in to a listing must also opt in on the new credential platform, so a holder missing from a search may simply not have opted in.

ASCA membership

The American Society of Consulting Arborists lists members in a "Find a Consulting Arborist" directory, according to its members brochure. The brochure says membership needs at least five years of experience in arboriculture plus one of the education routes it lists, and that earning 30 continuing education units every two years is required to keep membership. It says ASCA is the only arboricultural association that requires both a minimum number of years of experience and education. This is a person credential for consulting work. It says nothing about whether a crew's gear or systems have been inspected. See becoming a consulting arborist for the wider picture.

Canada

Companies in Canada can apply to TCIA Accreditation, as described above. ISA Ontario says an individual must have experience, pass an exam, renew every three years, continue their education and sign a code of ethics to become ISA Certified. That is the ISA credential, not a provincial company scheme.

United Kingdom

ARB Approved Contractor

The Arboricultural Association says on its ARB Approved Contractor page that this is the only comprehensive accreditation scheme for professional tree surgery businesses in the United Kingdom. It says the industry is not regulated by government but has a high accident potential. An approved contractor is a business assessed by the Association, not an individual. The page says the scheme gained ISO 9001 (UKAS) accreditation in 2012 and is registered with SSIP, and that it is increasingly demanded by local authorities and other large organisations.

The rules sit in the Association's scheme handbook (May 2023). It sets out the rules. These are the points a reader is most likely to look for.

Topic	What the handbook says
Who can apply	A business of at least two people, which may be a sole trader and a subcontract labourer, with no maximum size
Trading history	At least two years, which the Association can waive in some circumstances
Named Manager	At least five years of experience in arboricultural contracting; the Association must be told within 28 days if the Manager leaves
Insurance	Public liability of £5m or higher; employers' liability to a level matching the business, usually £10m
Cycle	A repeating two-year cycle: assessment or reassessment in one year, a desktop audit in the next
Certificate	Expires one year after issue; renewal depends on the audit and reassessment
First assessment	Usually 8 to 10 weeks after application when documents are in order

The Association's standards document (February 2024) says the modules on sites, yard and workshop are assessed by an assessor who visits, and the other modules are assessed remotely from evidence the contractor submits. It says the live worksite at an initial assessment must include rigging operations, and at a reassessment must include aerial tree work operations. Completed pruning is judged against BS 3998. The worksite check includes a site-specific risk assessment covering emergency and rescue planning. The standards are reviewed every year.

The handbook also says two technical standards apply to amenity businesses, one for fewer than five staff and one for five or more. Tree reports and advice are outside the scheme. For the scheme's utility work, the handbook lists five sectors: rail, electrical, waterways, telecoms and high-speed roads.

Enforcement is stated too. The handbook says contractors are normally audited annually, that the Association may reassess or carry out spot checks at any time without prior notification, and that a successful prosecution is a ground for early reassessment. An upheld complaint can lead to suspension or expulsion. A contractor who fails is removed from the online directory immediately. A business falsely claiming approval is asked to stop using the logo and is reported to its local Trading Standards department.

The Association's directory page says to search by business name or postcode, and that a business not on the online register is not an Approved Contractor. The handbook also says that a contractor outside the scheme is not necessarily a poor one. The choosing an arborist page says individual qualifications are typically administered by NPTC or Lantra and may be shown by an ID-style card or certificate, and recommends public liability cover of at least £5m.

The Association's 2025 fee sheet, covering 1 January to 31 December 2025, listed a micro business of one to five people at £650 plus VAT for an initial assessment or reassessment and £375 plus VAT for the annual scheme fee.

Registered Consultant

The Association's Registered Consultant scheme applies to an individual, not a company, according to its application guide (May 2026). It has run since the mid-1970s. Applicants must hold an arboricultural qualification at RQF Level 5 or above, be Professional or Fellow members of the Association, have at least five years of relevant experience at an advisory level, and hold professional indemnity insurance of at least £1 million. The portfolio is five report modules, one of them compulsory, written within three years before applying. Two assessors score it independently. A quality assurance document says one sample report from each consultant is reviewed every five years, from four submitted reports. Fees and the full assessment route are on the consulting arborist guide.

TrustMark

TrustMark calls itself the only UK Government-Endorsed Quality Scheme for work carried out in and around the home, and says it operates under a licence from the Department for Business and Trade. On its who we are page it says it works through scheme providers that are accreditation bodies and trade associations, and its scheme provider list includes the Arboricultural Association. The Association's 2025 fee sheet calls TrustMark an optional add-on to scheme membership. TrustMark says its scheme providers license and work with registered businesses to keep standards of technical competence, trading practices and customer service, and that a scheme provider may suggest an independent alternative dispute resolution provider for a complex dispute.

Another name appears in contractor adverts. SSIP says on its home page that it does not carry out assessments directly, its member schemes do, and it offers a portal where an assessment can be checked. The ARB scheme handbook says SSIP accreditation is awarded automatically after the annual audit for contractors that are not utility contractors.

Australia

Queensland Arboricultural Association register

The Queensland Arboricultural Association keeps a register of approved contractors and consultants. Its approved arborist page says the register responds to demand from the public and from local and state government for help finding qualified arborists. It also says the association has not assessed the quality of work carried out by those listed and makes no claims on their behalf, other than that they have met the criteria.

Register	Criteria on the page
Approved Contractor	Teams of at least three people, at least two holding an AQF Certificate III in Arboriculture; proof of training at three events per year; aerial rescue at least once a year, with proof
Approved Contractor, paperwork	First aid certificate, general safety induction, insurances, a safety policy, an environmental policy, and a statutory declaration that employee benefits are paid
Approved Consultant	A Diploma of Arboriculture at AQF Level 5 for all consultants; at least three reports written within five years before applying; risk assessment cannot be hired or subbed out

The association's contractor application form shows an annual charge of AU$1,000 for a contractor of one to five employees. Its consultant application form shows AU$750 a year for an individual consultant.

Arboriculture Australia registered membership

Arboriculture Australia is the national body. Its join page says that in an unregulated industry, a Registered Membership identifies a qualified professional who maintains up to date knowledge and ethical practices. The registered levels are Practicing Arborist, Consulting Arborist, or both, each priced as general membership plus AU$210, with prices quoted exclusive of GST. The page says these memberships have prerequisites and need approval, and that only registered members appear in its Find an Arborist directory. These are person memberships, not company approvals.

The association's continuing education policy (February 2024) sets required units each year: 6 for Practicing Arborist, 12 for Consulting Arborist and 18 for both. It says no units are needed when first applying. The registered member code of ethics (2024) requires compliance with codes of practice, Australian Standards and the Minimum Industry Standards, and asks members to report their own conduct that may breach the code. The Minimum Industry Standards page says the books are produced jointly by Arboriculture Australia and the New Zealand Arboricultural Association.

New Zealand

NZ Arb runs Registered Master Arborists NZ. Its application guide (version 6.3, August 2025) says the programme was set up in 1993 and was formerly the NZ Arb Approved Contractor Programme, then renamed in 2022. A Registered Master Arborist is a contracting business, not a person, and the register carries no ranking. The programme page says it is increasingly becoming a prerequisite for local authorities and commercial organisations.

Topic	What the guide says
Eligibility	A company with a qualification equivalent to NZQA Level 4, trading three years, or five years trading with or without qualifications, or equivalent shown
Crews	Where the principal is absent, each crew needs a Level 4 equivalent plus two years after qualifying, or five years of experience
Assessed	Client service, health and safety systems, codes of practice, plant, staff records, standards and insurance
Term	Up to five years, with an audit of each holder in the third year; renewal applied for at least 90 working days before expiry
Fee	NZ$1,300 a year excluding GST, covering the initial assessment, the mid-term audit and corporate membership

Applicants must be corporate members of NZ Arb. The steps are an expression of interest, a published notice of intent with two weeks for objections from members, a portfolio review and then an on-site assessment. Status can be suspended or lost for a breach of the code of conduct, failing to keep the criteria, or conduct that brings the programme into disrepute. NZ Arb also keeps a find an arborist page for the register.

What none of these schemes are

None is a license to work. ISA says so for its credentials, and the UK and Australian bodies call their industries unregulated.
Most are voluntary and paid for. A business outside a scheme may be fully qualified, as the UK handbook itself says.
Business schemes assess a business against set criteria, not every job it does. QAA says in plain words that it has not assessed the quality of listed members' work.
Person credentials show one individual's status, not the company that advertises with their name.

For insurance questions that sit beside these schemes, read insurance cover. For the bodies behind them, read associations and reading.