Quotas and service limits

IBM Cloud Transit Gateway enforces quotas and service limits on the resources that you can create. These limits are set per account or per gateway and represent the maximum values supported in the current release.

IBM Cloud Transit Gateway service limits
Service limit	Default
Number of transit gateways	10 gateways per account, 5 gateways per region
Number of connections per transit gateway	10 IBM Cloud VPC connections 5 IBM Cloud classic connections 5 IBM Cloud Direct Link connections 5 Power Virtual Server connections
Number of prefixes per connection	50 prefixes for VPC connections 120 prefixes for classic connections 120 prefixes for GRE connections 120 prefixes for Direct Link connections 120 prefixes for Power Virtual Server connections
Number of connections with prefix filters	2 connections with prefix filters per gateway
Number of prefix filters per connection	10 prefix filters per connection
Number of GRE tunnels per transit gateway	12 GRE tunnels per gateway
Number of unique base networks targeted by unbound GRE tunnels per transit gateway	5 unique base networks targeted by unbound GRE tunnels per gateway

You can open an IBM Support case if you need your service limits expanded.