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Build a multi-step approval chain that tracks its own progress

Send an expense claim through two approvers in sequence, using AI to flag anything unusual before it reaches a human, and keep a live record of exactly where each claim is stuck.

45 minAdvanced13 steps

What this looks like

One step on screen at a time. Read it, do it, tap Next.

Build a multi-step approval chain that tracks its own progress

Step 1 of 13

01 / 13n8n Form Trigger

Build the claim submission form

Create a workflow and add an n8n Form Trigger for employees to submit a claim.

Checkpoint

Submitting the form produces a complete item.

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Before you begin

Tick these off as you sort them. Stopping halfway to create an account is how a fifteen-minute build becomes an hour.

0 of 10 ready

Ticks are saved on this device, so you can come back to them.

  • Know-how

    Decide exactly who approves first and who approves second, and what happens if either rejects. Draw it out before you build it.

  • API key

    Used to flag claims that look unusual — high amounts, vague descriptions, or mismatched categories — before a human reviews them.

  • Have ready

    Columns: ClaimID, Employee, Amount, Stage, Status, Approver1, Approver1Decision, Approver2, Approver2Decision, Flagged.

  • Have ready

    The first approver is usually a line manager; the second is usually finance. Confirm both people are expecting this change.

  • Account

    Used to record and update the chain's progress after every decision.

  • Account

    Both approvers receive their requests from this address, in sequence rather than at the same time.

  • Time

    This is one of the more involved builds in the library — the state tracking takes care to get right.

The basics — ticked once, remembered everywhere

  • Account

    Either the hosted version or a self-hosted install. Everything here works the same on both — the only visible difference is the shape of your webhook URLs.

    Create a workspace
  • Know-how

    Adding a node, connecting two of them, and pressing Execute. If any of that is new, the free primer covers it in about ten minutes.

  • Credential

    You will paste at least one secret during setup. A password manager beats a notes app, and it stops you pasting a live key into a chat window by accident.

The shape of the workflow

The nodes you will end up with, left to right, in the order you add them.

n8n Form TriggerCodeOpenAIGmailn8n Form TriggerGoogle Sheetsn8n Form TriggerGmail
The finished Build a multi-step approval chain that tracks its own progress workflow on the n8n canvas4 things to set here
  1. 1n8n Form Triggerthe trigger — everything starts here
  2. 2CodeGive the claim an ID and initialise its state
  3. 3OpenAIScreen the claim with AI before it reaches a human
  4. 4GmailLog the claim and send it to the first approver
The finished workflow on the n8n canvasTap to enlarge

Skip the node hunting

Import a starter file with every node for this build already on the canvas, named after its step and wired in order, each one carrying a sticky note with the values to enter. You still connect your own accounts and fill the fields — that is what the walkthrough takes you through — but you never start at a blank canvas.

In n8n: Workflows → Import from file.

Included with the library

What you will build

Jump straight to any step, or print the list and tick it off beside your n8n tab.

If something goes wrong

Everything ready?

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