---
title: "Why does the tracking number change during a visit?"
url: "https://calltracking.au/help/numbers/number-changes-during-visit"
summary: "A visitor holds their tracking number while they're active on the website and for about 2 minutes after, and then it can go to another visitor. When they come back, they can see a different number, and their visit is still tracked."
type: explainer
audience: customers
products: ["Number pools", "Tracking script"]
---

# Why does the tracking number change during a visit?

**Short answer:** A visitor holds their tracking number while they're active on the website and for about 2 minutes after, and then it can go to another visitor. When they come back, they can see a different number, and their visit is still tracked.

**Applies to:** Number pools, Tracking script

## How long does a visitor keep their number?

When a visitor opens a page, Call Tracking gives them a number from the pool and holds it for them for 2 minutes. Every page they open renews the hold, and while the page stays open and they're using it, the tracking script keeps renewing it in the background.

So a visitor who's reading or browsing keeps the same number, and the number they see is the one they dial. To learn more, see [How numbers are assigned](/docs/attribution/#how-numbers-are-assigned).

## Why does it change?

The hold lapses about 2 minutes after the visitor stops using the website: they leave it, switch to another tab for a while, or their computer goes to sleep. Browsers also slow down pages in background tabs, which can delay the renewal. Once the hold lapses, the number can go to another visitor.

When the visitor comes back and opens a page, they get a number again, and it's usually a different one. If they go back to the page they left open instead, the tracking script checks in soon after they start using it again, and if their number has changed, the page switches to the new one.

## Does it affect tracking?

The visit itself ends only after 30 minutes without activity, so a call on the new number is still linked to the same visit: the same landing page, campaign and source.

A call to the old number, from a number written down earlier or from a tab left open before it updates, is different. If no one holds that number when they call, the call has no attribution. If another visitor holds it by then, the call can be credited to that visitor. To learn more, see [A call shows no attribution](/help/attribution/call-not-attributed).

## Will more numbers stop it?

No. This isn't a sign the pool is too small, and adding numbers doesn't keep a returning visitor on their old number. A pool's **Health** measures something else: how often visitors on the website at the same time have to share a number. To learn more, see [How many tracking numbers does a website need?](/help/numbers/how-many-numbers)

## Related

- [How many tracking numbers does a website need?](https://calltracking.au/help/numbers/how-many-numbers.md)
- [A call shows no attribution](https://calltracking.au/help/attribution/call-not-attributed.md)
- [How numbers are assigned](https://calltracking.au/docs/attribution/#how-numbers-are-assigned)

---

Web version: https://calltracking.au/help/numbers/number-changes-during-visit