> [!CAUTION]
> **Caution:** This documentation is for Google Ads API **v24** . The latest active version is [**v26**](https://developers.google.com/google-ads/api/reference/rpc/latest/ReachPlanBuyingMethodEnum.ReachPlanBuyingMethod).

The reach plan buying method for an ad product.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v24/enums/reach_plan_buying_method.proto)

| Enums ||
|---|---|
| ## `AUCTION` | Bidding on ads with a target CPM. |
| ## `RESERVATION` | Buying method that encompasses deal-based and instant reserve pricing. |
| ## `UNKNOWN` | The value is unknown in this version. |
| ## `UNSPECIFIED` | Not specified. |