FOAPAL

FOAPAL (fund, org, account, program, activity, location) is an accounting system used throughout McGill University. It is limited to organizations directly associated with McGill; faculties, professors, departments, services, and so on within McGill all have a FOAPAL number to charge and receive payments.
The EUS is not part of McGill (see What Isn't the EUS), and is therefore not entitled to a FOAPAL number.
The advantage of FOAPAL numbers is easy transactions with professors, departmental committees, university affairs, etc.; unfortunately the EUS does not have and will not have this feature in the forseeable future.

To send money: Check out the Cheque Reqs page to request a cheque to whomever you're looking to pay. Make sure you have a proper invoice before filing for a check!

To receive money: Simply request the persons you are dealing with write a check payable to the Engineering Undergraduate Society of McGill University

TL;DR The EUS does not have a FOAPAL.