Budgeting for Azure Service Bus

Hi @robm,

Assuming you’re talking about Standard Tier, you’ll have a base charge of $10 for all of your namespaces.
Next step is to look at what topology will be used. For Forwarding topology only a single queue is polled. For EndpointOriented topology, input queue and all subscriptions are polled. With Forwarding topology there’s a cost of auto-forwarding from subscriptions to input queue, but I’ll omit that as you’re referring to a scenario with no messages.

If there are no messages, your cost will be limited to number of connections and queues polls. Note that ASB service Standard tier has first 13M ops/m free. After that you pay based on number of operations.

ASB operations and connections costs are:

Brokered connections (Number of AMQP connections or HTTP calls to Service Bus.)

First 1K/month Included
Next 99K (1K–100K)/month $0.03 per connection/month
Next 400K (100K–500K)/month $0.025 per connection/month
Over 500K/month $0.015 per connection/month

Messaging operations (An operation is any API call to the Service Bus service)

First 13M ops/month Included
Next 87M ops (13M–100M ops)/month $0.80 per million operations
Next 2,400M ops (100M–2,500M ops)/month $0.50 per million operations
Over 2,500M ops/month $0.20 per million operations

Number of operations (pollings) in this case will depend on number of connections you’ll have opened (controlled by number of messaging factories) and number of clients per entity you’re using. In case you’re planning to use multiple namespace (for HA or DR), you’ll have to take that into consideration as well.

Calculation is very different if plan to use Premium Tier with $22.26 fixed rate per message unit (per day).