Why do Item Fulfillments and Item Receipts seem to both credit my COGS account and debit my Inventory Asset account? (shouldn't it be the other way around?) I would greatly appreciate any help in understanding what would cause this.

Are you doing Vendor Return Auths & (sales side) Return Auths? VRAs will have Item Fulfilllments and RAs will have Item Receipts that are opposite accounting impact of regular ones. I'd check your Created From field to see if the ones that look backwards are associated with returns.

I guess you have negative inventory level for that item.

... it's both. First of all thanks for your replies, I really appreciate your help with this. It looks like three of the four cases that were called into question are linked to a VRMA record, so those are returns and the accounting should be working as you said, backwards. And the other record that they brought up is an Item Receipt on a PO where out of 36 items the only one that seems to have any landed cost details is in a negative quantity for the location on the PO. What I find strange is that none of the items are being accounted for in the expected way. It's like the COGS is only ever being credited and the Inventory Asset is only ever being debited. What needs to be set on the PO to ensure that the items received are correctly processed?

Item Receipts shouldn't be crediting COGS, they should be crediting Inventory Received Not Billed. Honestly I didn't think that was configurable that it won't go there, so I'm wondering if you do have some negative inventory issue like Arūnas mentioned.

... oh right, it's only credited on the bill once the bill process takes place right?

No COGS shouldn't be credited on the purchasing side at all. That's a sales side account. The bill would clear out Inv Received Not Billed and credit AP. Exception would be the vendor returns. If COGS is getting hit on the purchasing side for "regular" POs, you probably have some config problem on your items. Or maybe the Landed Cost you mention. I'm not very familiar with LC.

oh hmm, thank you for clearing up my misunderstanding on that. I don't see any mention of Inventory Received Not Billed, does that show up on the receipt somewhere? I'll have to take another look at LC to make sure that's not something that's throwing things off as well I suppose

In case of negative inventory the COGS account is hit because there is a wrong or zero amount in the Sales order fulfillment or Invoice transactions (Inventory transfer also affects it). Keep in mind that when automatic cost recalculation finishes these COGS amount will be cleared out. But this statement is valid if inventory goes to positive (or zero) side only. If it stays on negative side then COGS account will remain in purchase transaction.