Dynamics 365 Business Central – Why do you need to specify posting groups on G/L codes?


Since I’ve been working with Dynamics 365 Business Central I’ve loved the concept of posting groups. As a way of a very brief background, posting groups are used by Dynamics 365 Business Central to gather the required G/L codes when you post a transaction. Therefore you add posting groups to entities like Customers, Vendors, Bank Accounts, Item and also more interestingly G/L codes.

Coming from a Dynamics GP background I could understand why posting groups where needed on all entities, with the exception of G/L codes? Surely if I specify a G/L code on a transaction or journal, this is the G/L code I want to post to?

In this post I hope to shed some light on why the system still requires posting groups on G/L Codes.

A Sales Transaction using a G/L Code

As way of an example lets imagine we are adding the Sales Invoice using a G/L code as per below:

This transaction looks fairly straight forward. We are posting a Sales Invoice with a revenue code of 10100 therefore we expect G/L entries of Debit Debtors and Credit this Revenue code. With this in mind why would we need posting groups defined on the G/L code?

Ok, that’s a fair point, so let’s change the transaction ever so slightly and add some line discounts.

So now we have added line discounts we need a posting to the “Sales Discount” G/L code. However how is the system going to select the correct G/L code?

You guessed it, the answer is using Posting Groups.

So, if we look at the G/L card for G/L code 10100 we can find the product posting groups:

As this is SERVICES the system will use this, in combination with the “General Business Posting Group” from the Customer card, to select the relevant discount code using the “General Posting Setup” window, in this case 10300.

Without this information the transaction would fail to post. This is why the system is requiring you to enter posting groups onto G/L codes. They are needed so the system has a method of gathering other G/L codes that might be needed on the transaction.


This is likely obvious to seasoned Dynamics NAV and BC users however its something that took me a little while to fully grasp so I thought it worth sharing.

Hopefully anyone new to Dynamics 365 Business Central found this useful. (you can also read more about posting groups in this post)

Thanks for reading!