Additional Insured
What is Additional Insured?
An additional insured is a person or business added to someone else's liability policy by endorsement, so that policy answers a claim against them too. In field service it is what a commercial customer, property manager, or general contractor asks for on your general liability policy before you are allowed on site: they want your insurer to defend and cover them for claims arising out of your work. It is not the same as the certificate holder, who only receives a copy of your certificate of insurance and gains no coverage from it. No single national definition governs the term, so what you actually grant is whatever the endorsement form attached to your policy says, which is why the form and its wording matter more than the certificate that reports it.
On commercial work the request arrives as a line in the customer’s contract: name us as additional insured on your general liability policy. It is a step beyond proving you are covered. The certificate of insurance reports what your policy already says; the additional-insured endorsement changes the policy itself, so the customer is protected under your coverage for claims arising out of your work.
Regulators publish less on this term than operators expect. The NAIC’s glossary of insurance terms defines “insured” and “named insured” but has no entry for additional insured, and state consumer glossaries stop at the mechanism: Washington’s Office of the Insurance Commissioner defines an endorsement as “a written form attached to the policy that changes the terms of the policy to fit special circumstances.” So the definition follows the endorsement wording generally rather than any regulator’s text: the form your carrier attaches decides who is covered, for what work, and for how long. Ask your agent which form is going on the policy, and ask what the endorsement costs before you agree to provide it, because carriers price it differently and no regulator publishes a rate.
Two habits follow. Put the insurance requirement in the agreement itself rather than in email, which is what the clause set at service agreement clauses is for, and what a recurring commercial account carries in the preventive maintenance agreement template. And treat the policy behind the endorsement as a real cost of commercial work: the pest control business insurance guide walks through the coverages the endorsement is attached to. What the endorsement has to reach differs by trade, which is why an electrical contractor’s completed-operations exposure and a detailer’s responsibility for the customer vehicle in their care produce very different conversations with the same agent.