Private services access

This page provides an overview of private services access.

Google and third parties (together known as service producers) can offer services that are hosted in a VPC network. Private services access lets you reach the internal IP addresses of these Google and third-party services by using private connections. This is useful if you want your VM instances in your VPC network to use internal IP addresses instead of external IP addresses. For details about using private services access, see Configure private services access.

Private services access requires you to first allocate an internal IPv4 address range and then create a private connection. An allocated range is a reserved CIDR block that can't be used in your local VPC network. It's set aside for service producers only and prevents overlap between your VPC network and the service producer's VPC network.

The private connection links your VPC network with the service producer's VPC network. This connection allows VM instances in your VPC network to use internal IPv4 addresses to reach the service resources. Your instances can have external IP addresses, but external IP addresses are not required for, and are not used by, private services access.

If a service producer offers multiple services, you only need one private connection. When you create a private connection, you use the Service Networking API to create it. However, Google Cloud implements this connection as a VPC Network Peering connection between your VPC network and the service producer's VPC network. Your VPC network shows it as a peering connection, and to delete the private connection, you must delete the peering connection.

Using IPv6 address ranges with private services access is not supported.

You can use private services access only with services that support it. Check with the service producer before creating a private connection.

Service producer network

On the service producer's side of the private connection is a VPC network, where your service resources are provisioned. The service producer's network is created exclusively for you and contains only your resources.

A resource in the service producer network is similar to other resources in your VPC network. For example, it's reachable through internal IP addresses by other resources in your VPC network. You can also create firewall rules in your VPC network to control access to the service producer's network.

For details about the service producer side, see Enable private services access in the Service Infrastructure documentation. This documentation is for your information only and is not required for you to enable or use private services access.

Private services access and on-premises connectivity

In hybrid networking scenarios, an on-premises network is connected to a VPC network either through a Cloud VPN or Cloud Interconnect connection. By default, on-premises hosts can't reach the service producer's network by using private services access.

In the VPC network, you might have custom static or dynamic routes to correctly direct traffic to your on-premises network. However, the service producer's network doesn't contain those same routes. When you create a private connection, the VPC network and service producer network exchange subnet routes only.

The service producer's network contains a default route ( that goes to the internet. If you export a default route to the service producer's network, it is ignored because the service producer network's default route takes precedence. Instead, define and export a custom route with a more specific destination. For more information, see Routing order.

You must export the VPC network's custom routes so that the service provider's network can import them and correctly route traffic to your on-premises network. Update the VPC peering configuration associated with the private connection to export custom routes.


Before you configure private services access, understand the considerations for choosing a VPC network and IP address range.

Supported services

The following Google services support private services access:


In the following example, the customer VPC network allocated the address range for Google services and established a private connection that uses the allocated range. Each Google service creates a subnet from the allocated block to provision new resources in a given region, such as Cloud SQL instances.

Private services access (click to enlarge)
  • The private connection is assigned the allocated range. From this allocation, Google services can create subnets where new resources are provisioned.
  • On the Google services side of the private connection, Google creates a project for the customer. The project is isolated, meaning no other customers share it and the customer is billed for only the resources the customer provisions. Google also creates a VPC network in this isolated project and connects it to the customer network by using VPC Network Peering.
  • Each Google service creates a subnet in which to provision resources. The subnet's IP address range is a CIDR block that comes from the allocated IP address range. The CIDR block is chosen by the service, and typically has a /29 to /24 IP address range. You cannot modify the service producer's subnet. A service provisions new resources in existing regional subnets that were previously created by that service. If a subnet is full, the service creates a new subnet in the same region.
  • After the subnet is created, the customer network imports routes from the service network.
  • VM instances in the customer's network can access service resources in any region if the service supports it. Some services might not support cross-region communication. See the relevant service's documentation for more information.
  • The Cloud SQL instance is assigned the IP address In the Customer VPC network, requests with a destination of are routed to the private connection over to the service producer's network. After reaching the service network, the service network contains routes that direct the request to the correct resource.
  • Traffic between VPC networks travels internally within Google's network, not through the public internet.


For private services access pricing, see Private services access on the VPC pricing page.

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