Almost without exception. Once you accept that, intercompany stops being a fortnight of archaeology and becomes a sorting problem you can finish before lunch.
The reason it feels harder than that is the order most teams work in. They open the mismatch, then try to understand the transaction. That is backwards and it is why the same difference gets investigated three months running.
Sort first, investigate second
For any intercompany balance that does not agree, there are four possible causes and they are not equally likely.
Timing. Entity A raised the recharge on the 30th; Entity B booked it on the 2nd. Nothing is wrong. Both sides are correct at their own cut-off and the difference will clear itself next month. In most groups this is the majority of differences by count.
FX. Both sides booked the same transaction, at the same time, at different rates — because one used the spot rate on the invoice and the other used the month-average from the policy or because the policy exists but is applied inconsistently at one entity. The amounts differ; the transaction is the same. This is usually the majority by value.
One side missing. A genuine omission. Rarer than people expect and the only one of the four that is straightforwardly an error.
Different classification. One side booked a recharge as an expense, the other as an intercompany receivable. The group total is fine; the elimination breaks. This is the one that quietly corrupts consolidation for years.
How to tell which in about a minute
Take the difference and ask three questions in order.
Does it disappear if you move the cut-off by a few days? Re-run both sides at a date a week later. If the difference vanishes, it is timing. Stop. Book nothing, note it, move on.
Is the difference proportional? Divide the two amounts. If the ratio is close to the FX movement over the period — and especially if the same ratio appears on several unrelated balances — it is FX. The fix is a rate policy, not a journal.
Does one side have a document the other doesn’t? Now and only now, is it worth opening invoices. If both sides have the document, you are looking at classification, not omission.
Three questions, in that order, resolve the large majority of intercompany differences without anyone opening a ledger. The reason it usually takes a fortnight is that teams start at question three.
Why it gets worse every month
Intercompany differences compound in a specific way: the ones you resolve get resolved and the ones you cannot get carried. After a year of carrying, the opening balance contains a sediment of old differences nobody alive can explain and the first thing every new group accountant does is decide not to touch it.
The only durable fix is frequency. A difference found on the day it arises has a document, an author and a memory attached to it. The same difference found eleven months later has none of those and costs perhaps twenty times as much to resolve — if it can be resolved at all.
This is the real argument for matching intercompany daily rather than at consolidation. Not elegance. The fact that a difference has a short half-life and after that you are doing archaeology.