> [!NOTE]
> **Note:** If you are running an [A/B experiment using the Google Ads UI](https://support.google.com/google-ads/answer/12997711), we recommend you complete the process through the UI rather than using the API.

Once you are happy with the performance of your new campaign,
you should complete your upgrade to Performance Max by choosing one of the
following options.

## Move budget to Performance Max and remove your existing campaign

Once you are ready to move budget to Performance Max, you will need to adjust
the budget and remove the existing campaign that it replaces. When you do this,
remember that you can still check the historical performance through reporting
by setting the
[`campaign.status`](https://developers.google.com/google-ads/api/fields/v26/campaign#campaign.status)
to `REMOVED` in the `WHERE` clause of your
[query](https://developers.google.com/google-ads/api/docs/query/overview).

To move the entire budget to Performance Max, you will need to
[create a new budget](https://developers.google.com/google-ads/api/docs/campaigns/budgets/create-budgets) for your
Performance Max
campaign with the appropriate spend and
[set the campaign budget](https://developers.google.com/google-ads/api/performance-max/create-budget).
For Performance Max campaigns, this budget cannot be shared.

Then you should pause or remove your existing campaign as described in the
[remove campaign code example](https://developers.google.com/google-ads/api/samples/remove-campaign).

> [!NOTE]
> **Note:** It is worth keeping a record of the [campaign ID](https://developers.google.com/google-ads/api/fields/v26/campaign#campaign.id) of both campaigns so you are able to understand the continuity of performance.

## Move budget to Performance Max and retain your existing campaign

There are scenarios you might want to keep your existing campaigns serving.
Perhaps they have different targeting settings or perhaps they
contain a configuration that serves a specific purpose. In this case, you might
want to increase the budget for the Performance Max campaign, but retain some
proportional budget for campaigns you keep enabled.

To move more budget to Performance Max, you need to
[create a new budget](https://developers.google.com/google-ads/api/docs/campaigns/budgets/create-budgets) for both
campaigns with the appropriate spend and
[set the campaign budget](https://developers.google.com/google-ads/api/performance-max/create-budget).
For Performance Max campaigns, this cannot be a
[shared budget](https://support.google.com/google-ads/answer/10487241).

> [!NOTE]
> **Note:** To understand how Performance Max interacts with other campaigns, see this [support article](https://support.google.com/google-ads/answer/13810170)