Notifications of Change (NOCs)
Overview
When Check sends ACH payments on behalf of partners and employers, the Receiving Depository Financial Institution (RDFI) may return a Notification of Change (NOC).
A NOC is a courtesy notice provided by the RDFI, which means that the payment was processed successfully, but some piece of account information needs to be corrected before the next payment to avoid future delays or returns.
NACHA rules require that bank accounts flagged by NOCs be updated by Check within 6 banking days.
Why NOCs matter
| Stakeholder | Why you should care |
|---|---|
| Employers / Payroll admins | Prevent payroll delays, avoid NACHA fines, reduce support tickets, and maintain employee trust. |
| Employees | Ensure funds continue to land in the right bank account on time. |
| Partners | Maintain high payment‑success metrics and reduce manual support work. |
How an ACH payment becomes a NOC
- Payroll file sent – Check originates an ACH entry with the bank details provided by our partners.
- Payment posts – Funds are deposited or withdrawn from a bank account.
- Bank detects an issue – The RDFI sees outdated or incorrect data (e.g., routing number changed) and generates a NOC via the ACH network.
- Check receives the NOC and makes or suggests the required correction.
Most common NOC codes
From a sample of 5,000 recent NOC webhooks, 92 % were covered by just three codes.
| NOC Code | Meaning | Count | % of Total |
|---|---|---|---|
| C01 | Incorrect bank account number | 1,817 | 36.34 % |
| C02 | Incorrect transit / routing number | 1,839 | 36.78 % |
| C05 | Incorrect payment (transaction) code* | 979 | 19.58 % |
| C03 | Incorrect account and routing number | 304 | 6.08 % |
| C06 | Incorrect account number and transaction code | 46 | 0.92 % |
| C07 | Incorrect routing #, account # and transaction code | 15 | 0.30 % |
| C04, C08–C12 | Rare (< 0.1 %) | – | – |
*C05 tip: This usually means a checking account was mis‑coded as savings or vice‑versa. See FAQ.
How Check now handles NOCs
| Step | What happens |
|---|---|
| 1 | Check receives the NOC from our payments processor. |
| 2 | Check parses the corrected data (e.g., corrected_account_number, corrected_routing_number, corrected_transaction_code) out of the NOC |
| 3 | Check updates the bank account record in real‑time, and sets the last_noc_correction_at field to the time when we processed the NOC. |
| 4 | Check notifies partners of the change via the existing bank_account.updated webhook. |
| 5 | The bank account remains enabled — future payroll runs use the corrected info automatically, without any action required by the employee, employer, or partner. |
What employers & employees need know
- Deposits that triggered NOCs are successful.
- Employers and employees don’t need to do anything to handle NOCs in most cases. Check will apply the fix instantly.
- If Check cannot auto‑update (rare), we will disable the bank account and send a Zendesk ticket to the partner for review.
- Future paychecks will continue normally once the correction is on file.
Updated 2 days ago