Alternative Market
Browse resources to service your existing WC clients insured with our Alternative Markets.
Contact Info: Service/Billing/Claims
Agent Inquiries can be directed to Number One Insurance. Please contact Michelle St. Angelo at or 508-634-7364.


A.I.M. Mutual Insurance Companies

  • Online:  Customer Service Center
    • Create a Portal Login
    • Injury Prevention & Worksite Wellness Resources & Tips
    • Phone:  (800) 876-2765
  • Report a Claim:  Online Report
    • Fax:  (781) 270-5599
    • Phone:  (866) 270-3354
    • Mail:  P O Box 4070, Burlington, MA 01803



All carrier correspondence for your insured is forwarded to your agency by the carrier or Number One with directions to forward to the client if required.


Only the appointed agent is allowed to make coverage/named insured change requests. All endorsement, cancellation, reinstatement, loss run and other such requests should be requested in writing to Number One Insurance to communicate with the assigned carrier.


Renewals are generally processed 30 days prior to the expiration of the current in-force policy.

 Certificates of Insurance

Agents may issue a certificate of insurance.  

  1. Confirm policy is in force by calling the automated billing center at: 877-528-7878.Please note: If asked to verify the agency on the account – the insured’s policy declaration page reads Mackinaw Underwriters Inc.
  2. Provide a copy to Michelle St. Angelo at or by fax 508-634-2930. 
  3. We will forward this certificate on to the carrier.
Audit Disputes

Forward to the carrier audit department all copies of the 941's issued throughout the policy term and a letter from the insured asking for a review of the audit.


If insured needs assistance contacting the auditor, please contact Michelle St. Angelo and she will research and provide their contact information.

 Request for Reinstatement

Provide a signed request for reinstatement on the insured's letterhead that includes:

  1. Name and address of insured
  2. Policy number
  3. Cancellation date
  4. Statement of no losses between date of cancellation through current date
  5. Signature of owner/officer with printed name & title

Forward to Michelle St. Angelo at or by fax 508-634-2930.

 Broker of Record Requests

Please include the following on the insured's letterhead:

  • The current policy number and effective date.
  • A request naming BOTH Number One Insurance AND your agency as the Broker of Record.
  • The Insured's Signature.
 Waiver of Subrogation

Alternative Market Application for Waiver of Subrogation

Application required and a premium is charged based upon type of waiver. Please note your request for a Specific or Blanket Waiver.


Aligned with the mission of MAIA, the Number One Insurance Agency, Inc. provides several niche retail markets as a benefit of membership. Experienced in-house staff along with key carrier partners, work to assist and service members with our insurance offerings...


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