Wanted to get info on how other banks with high volume commercial cash deposits handle CTR processing. We use an armored carrier to process deposits for us in areas where we don't have branches. We get an electronic file daily that breaks down cash/checks and use that for posting. What we are struggling with is the armored transport carrier has a 2 day window to actually verify the deposit amounts, so we regularly get vault deposit corrections. For instance, customer makes a $12K cash deposit on 8/10. File sent to us shows cash in of $12K, and we post this to customer's account on 8/10. Then when armored carrier verifies the deposit on 8/13, they send us a cash credit correction for $100. We post the correction with the date of 8/13. Customer sees that on their statement and the description relates it to the deposit on 8/10 that was declared as $12,000 but was $12,100 when verified. Let's also say the customer had another deposit on 8/13 for $15,000 cash. We've been reporting that for 8/13 there was $15,100 cash in (credit cash correction from 8/10 posted on 8/13, plus new 8/13 deposit of $15K cash). What do other banks do?

I'm not sure, but I'd see if you can back date the correction to the correct date it should have posted to the account.

At my former (much larger) institution, the CTRs for vault customers would not be reviewed until the cash has been verified. The customer still gets provisional credit of the $15,000 cash but the CTR department gives themselves two days after the deposit was made to review the CTR for filing and any corrections to the deposit. CTR is still filed within the 15 calendar days, but it is not reviewed next day and filed.
So in your example, the CTR for 8/10 would be reviewed on 8/13 after the correction has been made to the deposit amount and the CTR would be filed on 8/13 for transaction that occurred on 8/10.

At my former institution, the CTR department (which I was the manager of) would review the transactions 2-5 days after the posting, reconcile the CTRs and file all at once via batch on Friday for the week prior. We would update the transactions as necessary for accurate reporting.