Reporting Security Incidents

If you are a current supplier and need to report a security incident, please contact your primary Marsh & McLennan account contact by phone. In the event you are unable to reach such contact promptly, send an email to

Please include: (a) a description of the incident, including its impact; (b) the expected resolution time (if it has not already been resolved); (c) corrective measures to be taken, evaluation of alternatives and next steps; and (d) the name and phone number of the supplier representative for us to contact to obtain further information and updates.


Accounts Payable Contacts

Below are the appropriate Marsh & McLennan Companies, Inc.’s Accounts Payable contacts for purchase order and invoice statuses.

Marsh & McLennan Companies, Marsh, Guy Carpenter, Stars, VOSCO, ENCON (All countries except for Latin America):

Mercer, Oliver Wyman Group, NERA

For geographies not listed, please connect with your Marsh & McLennan Companies business contact for the appropriate contact information.

Supplier Payment Procedures

Marsh & McLennan Companies has partnered with Tungsten Network to provide a simpler way for suppliers to submit invoices. By joining the Tungsten Network, you will experience greater efficiencies from Marsh & McLennan Companies' Accounts Payable department. This initiative is key to our strategy moving forward and we are confident you will see significant benefits to your business.

  • Fast, guaranteed invoice delivery. Invoices are received automatically and securely against any valid MMC purchase order listed in the Tungsten portal
  • Early invoice data validation. Tungsten Network validates supplier invoice data at time of entry, streamlining approval
  • Greater visibility of invoice status.   Suppliers no longer need to chase invoices, but can instead see status at any stage
  • On-time payments.  Improves supplier cash-flow
  • Tungsten HelpDesk and Support. Suppliers have access to the Tungsten HelpDesk for invoicing support and assistance

Enroll in electronic invoicing with Marsh & McLennan partner Tungsten:

Marsh & McLennan Companies, Inc. (MMC) requires all suppliers to include a valid MMC purchase order (PO) number on every invoice.  Supplier invoice should match the PO line items to support reconciliation and payment. Invoices received without a valid MMC supplied purchase order number will be rejected and returned to the supplier without payment.

First-time Suppliers must complete a one-time setup process, initiated by the MMC business contact.  Communication during setup will be between the MMC Global Supplier Maintenance team and Supplier. Per company policy, the MMC business contacts cannot act as an intermediary in requested setup information. Setup may require information such as: W8/W9, banking details, sample invoice, remittance and PO delivery addresses. Upon receipt of all required information, supplier setup requires a minimum of 4 business days to complete so that MMC may conduct proper supplier validation.


Terms & Conditions

Where a master agreement is in effect between the supplier and Marsh & McLennan Companies, Inc., or the Marsh & McLennan Companies, Inc. affiliate that is the Customer, the terms of that agreement will govern all purchase orders. In the absence of any such agreement, purchase orders will be governed by Marsh & McLennan Companies, Inc.'s standard terms and conditions, except that purchase orders for the performance of Services or delivery of Goods in each of the countries listed below will be governed by the version of Marsh & McLennan Companies, Inc.’s standard terms and conditions translated into the local language for each country respectively (click on applicable country name for translation):


Prospective Suppliers

If you are a prospective supplier and would like to be considered for future opportunities with Marsh & McLennan Companies, please complete the Marsh & McLennan Companies, Inc. Supplier Registration Form below. Your information will be preserved within our Registered Supplier Database, which is referenced by our Global Sourcing and Procurement department for future opportunities.