Trails4 min read

Map sources

Give each place leads come from its own column mapping, so a new form or a new list with different columns reaches the trail's steps in the same shape.

By Operelio team · Updated October 20, 2026

On this page7
  1. 1.What a source is
  2. 2.When a new source arrives
  3. 3.The suggested mapping
  4. 4.Joining columns
  5. 5.Sources the trail remembers
  6. 6.Who can map sources
  7. 7.Frequently asked questions

What a source is

A source is one place leads come from, with its own set of columns: a webhook, the senders at one email domain, an API key, or a file upload. Two uploads with different columns, like an Apollo export and a Cognism export, are two sources. Only the column names are compared, so their order and capital letters don't matter.

The first source a trail takes in sets the trail's own columns. Leads and files from it go on as they arrive. When a source with columns the trail hasn't seen turns up, Map sources gives it a mapping onto the trail's columns, so every lead reaches the next step in the same shape.

It works for single leads from a webhook or email, and for files.

When a new source arrives

With Map sources off, a trail runs what arrives as it is. If a step can't run on a new source's columns, the leads or files are held, and a dashed Map sources tile appears first on the canvas, marked Suggested, not added yet. Click it to see the source's columns and a suggested mapping.

With Map sources on, a source the trail knows uses its mapping. A new source is mapped on its own when every column the trail reads is found without doubt. Otherwise its leads and files wait for you.

Either way, the held lead says: A new source arrived with different columns. Map its columns on the trail, or run it as it is. Nothing from that source reaches your CRM until you choose.

ButtonWhat it does
Add Map sources, or Use this mappingSaves the mapping for this source and turns Map sources on. Every lead and file waiting on the source goes on.
Run without mappingLets the source run as it is, the way the trail did before the tile. Every lead and file waiting on it goes on.

You decide in the Map sources panel on the canvas, not on the Leads tab. Once you do, the waiting leads leave the Held view on their own.

The suggested mapping

The panel lists the source's columns under From, each with a Trail column it fills. Change any of them in its menu, or pick Not used. An example value from the newest lead shows under each column name, for you only.

The suggestion comes from the column names alone: Operelio matches them against the trail's columns and its saved mappings. On Starter and above, Bridgeant suggests the columns that are left, from their names. It never sees a lead or a cell.

If nothing from the source fills a trail column, the panel names it: steps that read that column get nothing from this source.

Call this source renames it, up to 80 characters. New ones are named for where they came from, like Email from harborhall.com.

A mapping saves to the live trail straight away, so the panel can be changed only on the Live tab once a trail has gone live.

Joining columns

One trail column can be filled from two to five of the source's columns, joined in order with a space, like First name and Last name into Name. Under a mapped row, click Add a column and pick the next one. Empty parts are skipped. Not joined in the menu undoes it.

A source can have up to 10 joins, and each of its columns can be used once.

Sources the trail remembers

With Map sources on, the panel lists every source with how many leads and files it sent in the last 7 days. Each keeps its own mapping, and later leads and files from it use that mapping on their own.

Open a source to change its mapping, then click Save mapping. Forget this source makes its next arrival count as new again. The trail's own source can't be forgotten, and neither can one with leads waiting on it.

Remove Map sources turns the tile off. The trail keeps its sources.

A trail keeps up to 100 sources, and up to 10 waiting for a mapping. Past that, what arrives runs as it is.

Who can map sources

Only an admin can map a source, run it without mapping or remove the tile. Everyone else sees the panel read only.

Frequently asked questions

Does Map sources change my cells?

Only when you join columns. Otherwise it renames columns to the trail's own, and the values stay as they arrived.

Does a new sender at the same domain need mapping again?

Not if it sends the same columns. Email sources are kept by the sender's domain, so everyone at one company shares a mapping.

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