> ## Documentation Index
> Fetch the complete documentation index at: https://docs.arcuserp.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Document Numbering
> Use Document Numbering settings to control prefixes, digit padding, and next-number previews for future Arcus documents without changing numbers already issued.
Document Numbering changes future document numbers only. Existing orders,
invoices, quotes, purchase orders, checks, returns, payments, journals, and
inventory transfers keep the numbers they already received.
## Open Document Numbering
1. Open **Settings**.
2. Choose **Entity Settings**.
3. Open the **Documents and Email** group.
4. Choose **Document Numbering**.
## What You Can Change
Each row controls one document sequence. Arcus shows the readable document type,
the stored counter type, the prefix, the padding, the current value, and the next
number preview.
You can change:
* **Prefix**: the letters or text placed before the number.
* **Padding**: the minimum number of digits in the numeric part.
You cannot change:
* **Current value**: this is intentionally read-only so issued numbers cannot be
moved backward or reused.
## Common Counter Types
| Counter | Example use |
| ------------------- | ----------------------------------------------- |
| Sales Orders | Sales order numbers. |
| Invoices | Customer invoice numbers. |
| Quotes | Quote numbers before conversion. |
| Purchase Orders | Vendor purchase order numbers. |
| RMAs | Customer return authorization numbers. |
| Journal Entries | Journal entry numbers. |
| Account Numbers | Customer or vendor account numbers. |
| Vendor Bills | AP bill numbers generated by Arcus. |
| AP Payments | Vendor payment numbers. |
| Checks | Check numbers controlled by the check workflow. |
| Inventory Transfers | Transfer document numbers. |
| Vendor Returns | Vendor return numbers. |
| Refunds | Refund document numbers. |
## Edit A Counter
1. Find the document type you want to change.
2. Click **Edit**.
3. Update the prefix or padding.
4. Review **Next Preview**.
5. Click **Save**.
6. Create a safe draft document and confirm the number looks correct.
Prefix must be filled in and can be up to 20 characters. Padding must be a whole
number from 1 to 12.
## How The Next Preview Works
The next preview is calculated from the current value plus one. For example, if
the prefix is `SO-`, padding is `7`, and the current value is `123`, the next
preview is `SO-0000124`.
Changing the prefix from `SO-` to `ACME-SO-` changes future sales orders. It does
not rename `SO-0000123` or any earlier order.
**Never try to reuse issued numbers**
Duplicate document numbers create customer confusion, accounting cleanup, and
audit questions. If the next preview is already in use, stop and review the
history before issuing new documents.
## When To Change Numbering
Good reasons:
* A new entity needs a company-specific numbering style before launch.
* A migrated business wants future numbers to match legacy formatting.
* A prefix is unclear and should be made more specific.
* Padding should be expanded before the sequence grows past the current width.
Bad reasons:
* Hiding a mistake in a previous sequence.
* Reusing a cancelled or voided number.
* Making a production system match a temporary test record.
* Changing check numbers without matching the physical check stock process.
## Multi-Admin Behavior
Document Numbering refreshes when another admin updates a counter. If you are
editing a row, Arcus avoids clobbering the row you are actively changing, but you
should still coordinate live numbering changes with other admins.
## What To Test After Saving
* Create a draft sales order, quote, purchase order, or invoice for the changed counter.
* Confirm the next number uses the expected prefix and padding.
* Confirm old documents still show their original numbers.
* If checks are involved, confirm the check register and physical check stock still align.
* If integrations import or export document numbers, confirm the downstream system accepts the new format.
## Common Blocks
* **Save is disabled**: the prefix or padding has not changed, the prefix is blank, or padding is outside the allowed range.
* **Next preview looks too short**: increase padding before saving.
* **Current value cannot be edited**: Arcus protects it so historical numbers are not reused.
* **A teammate sees a different value**: refresh the page after another admin saves.
* **External system rejected a new number**: review the prefix format and any integration rules that expect a specific pattern.
## Related Articles
Review the full Documents and Email group and how numbering fits with PDFs, templates, and quote behavior.
Create sales orders and confirm how order numbers appear in daily workflows.
Understand invoice creation, posting, sending, payment, correction, and voiding.
Review high-impact admin changes and compliance exports.