How approvals work
The approval system makes sure invoices, vendor credits, and approvable actions get reviewed by the right people before they finalize. Documents route automatically based on the policies you define.
Building blocks
The approval system has five components.
Policies
A policy is a named approval rule. For example, "High Value Invoice Approval" might require Controller sign-off on any invoice over $5,000. You can create as many policies as your organization needs.
Each policy carries a chain type:
- Invoice approval policies route extracted invoices to approvers.
- Email review policies route inbound emails to reviewers before they become invoices, so the team can vet or split an attachment-laden email before processing fires.
Conditions, chains, steps, and approvers work the same way for both chain types.
Conditions
Conditions are the criteria that decide which documents trigger a policy. Examples: "invoice amount greater than $5,000", "vendor is Acme Corp". When a document matches a policy's conditions, it enters the approval process. Conditions are optional. A policy with no conditions applies to every document of its type.
Chains
A chain is the sequence of approval steps that gets created when a document matches a policy. Each document gets its own chain.
Steps
Steps are the stages within a chain. A policy can have one step (single approval) or several sequential steps (Step 1: Controller, Step 2: VP). Each step completes before the next begins.
Approvers
Approvers are the users or groups assigned to each step. You assign groups when building the policy. Within a group, you choose whether any one approver can complete the step or all approvers must approve.
Chain types
The Approval policies page groups policies under three tabs by what they route. You pick the chain type when creating a policy.
| Tab | What it routes | When it runs |
|---|---|---|
| Invoice approvals | Documents (invoices, vendor credits, actions) | After validation passes, before ERP sync. This is the standard invoice approval flow that the rest of this article describes. |
| Invoice review | Validation results on a document (rule failures, hook failures, notices) | During validation, before approval. Decides who reviews and resolves the validation issues on a flagged document. |
| Email review | Inbound emails before any invoice is created from them | At ingest time, when an email arrives in your inbound mailbox. Decides whether to auto-create invoices from the attachments or hold the email for human review first. |
Email review policies have a different routing context than the other two: they evaluate against properties of the email itself — sender_email, sender_domain, receiving_inbox, subject, attachment_count — not against a document. Use them to gate suspicious senders, route by inbox, or auto-approve known partners.
All three tabs use the same building blocks (policies, conditions, chains, steps, approvers) and the same priority-order evaluation. The only difference is what they route and when.
Approval chains settings page with a list of chains, each tagged by its chain type: approval, validation, or email_review.
Priority order
Policies evaluate in priority order. Each policy has a priority number. Lower numbers mean higher priority. When a document is submitted for approval, Mod AI checks policies from highest priority to lowest and applies the first match.
If Policy 1 (priority 1) matches invoices over $25,000 and Policy 2 (priority 2) matches invoices over $5,000, a $30,000 invoice triggers Policy 1 because it is checked first.
See Editing and Reordering Policies for how to set priority.
What goes through approval
Not everything in Mod AI requires approval.
| Document type | Requires approval |
|---|---|
| Invoices | Yes. Routed through invoice approval policies before ERP sync. |
| Vendor Credits | Yes. Treated like invoices for approval. |
| Inbound emails | Optional. Email review policies can route an inbound email to reviewers before it becomes an invoice, so the team can vet, split, or reject an attachment-heavy email up front. |
| Actions | Yes. Some actions require approval before they execute. |
| Purchase Orders | No. Read-only data synced from your ERP. |
| Receipts | No. Read-only data synced from your ERP. |
Approval modes
Per entity, approvals run in one of two modes.
- Automatic. The system routes documents to the right approvers based on your policies. Recommended for most organizations.
- Manual. Users explicitly submit documents for approval. The system still uses your policies to build the chain, but documents do not route until someone submits.
Approval mode is per-entity in entity feature settings. Talk to your admin to change it.
The end-to-end flow
A typical automatic approval:
- An invoice is processed and ready for approval.
- Mod AI evaluates the invoice against policies in priority order.
- The first matching policy applies. A chain is created.
- The document routes to approvers in Step 1.
- Approvers are notified and can approve or reject from the approval list.
- When Step 1 is complete, the document moves to Step 2 (if there is one).
- After all steps complete, the document is fully approved and continues to ERP sync.
If a document is rejected at any step, it returns to the submitter for correction and can be resubmitted.
When the standard chain is not what you need
For one-off changes to a single invoice, use a routing override to alter that invoice's chain without touching the policy.
When building or editing a policy, use routing preview to simulate how a sample invoice would route through it before saving.
When an approver is unavailable, delegate approvals to a colleague for a date range.
When existing pending documents need to follow an updated policy, reroute them onto the current policies.