Cost Centers and Internal Orders both allow you to report on planned spending and compare it to actual revenue and expense postings for a specific department, program or project. Reporting is available down to the general ledger level of detail.
Key differences between the two accounts are outlined below:
Cost Centers are typically used for tracking ongoing, fiscal year based activities (i.e. May 1st to April 30th), while Internal Orders are used for short term activity tracking or for long term non-fiscal year based activities.
It is very important that when posting transactions either a Cost Center OR Internal Order is used, but not both. The risk of posting to both is inaccurate and possible duplicate reporting.