SAP very recently
announced the availability of a free tier offering for selected services in SAP Business Technology Platform as of 1st of July, 2021. Please see the blog posts by
anja.schneider and
riley.rainey for more details:
The great news is that SAP Cloud Transport Management (CTMS) is among the twenty front runner services available in this new plan. In this blog post I will describe how to enable the free tier for CTMS and what are the differences to the paid offering (besides being free...).
Prerequisites
Currently the free tier plans are available to Pay-As-You-Go (PAYG) and Cloud Platform Enterprise Agreement (CPEA) customers. All other new and existing customers can simply sign up for PAYG through the
SAP Store to get started.
Additionally you need a new or existing multi-environment subaccount in which you have not yet subscribed to SAP Cloud Transport Management. In this subaccount Cloud Foundry has to be enabled.
If you want to use the full functionality of CTMS including the use case to transport content archives directly in an application (for example from SAP Cloud Integration), you will also have to create a space in your Cloud Foundry environment.
Enable the free tier plan for CTMS
Basically you have to follow the steps described in the
documentation for setting up SAP Cloud Transport Management.
Here the first step is to entitle a multi-environment subaccount for subscribing to CTMS, free tier. You can do this on global account level or within the subaccount itself. I will show the configuration from global account level.

Configure entitlements from global account level
After clicking on 'Configure Entitlements' choose 'Add Service Plans'.

Start adding service plans
Scroll down to 'Cloud Transport Management' and select the 'free (Application)' plan. If you want to use the full functionality of CTMS including the use case to transport content archives directly in an application, you will also have to select the entry 'standard' (without 'Application'). If you want to create a service instance with limited authorizations you could alternatively also select the 'export' or the 'transport_operator' entry.
Make sure
not to select 'standard (Application)', because that would activate the payable version of Cloud Transport Management.

Select free service plan for Cloud Transport Management
Don't forget to save your newly created entitlement.

Save changes to entitlements
Subscribe to Cloud Transport Management
The next step is to subscribe to Cloud Transport Management. For that enter your subaccount you want to use for testing CTMS.

Open subaccount
Open 'Instances and Subscriptions' and click on 'Create'.

Create a subscription to CTMS
Select 'Cloud Transport Management' from the list of services.

Select CTMS from list
Make sure that the 'free' plan is selected and click on 'Create'.

Create free plan instance
It will take a few moments until the subscription is activated.

Subscription completed
Complete Configuration of CTMS
Now follow the instructions to complete the configuration as described in
the documentation of cTMS. This includes:
- Create role collections
- Assign roles to the role collections
- Assign role collections to users
- (optional) Create space in your subaccount
- (optional) Create and assign quota plan to space
- (optional) Create service instance
- (optional) Create service key
There is no difference in these steps as compared to the payable plan.
Use Cloud Transport Management
You are now ready to log on to the CTMS User Interface. To do this open the 'Instances and Subscriptions' view of your subaccount and click on the three dots in the line of the subscription to 'Cloud Transport Management'. Choose 'Go to Application'.

Start the CTMS UI
You might have to provide your username and password before the overview screen of CTMS opens.

Overview screen of CTMS
You can now follow the instructions to set up your transport landscape as described
here in SAP Help. This includes:
Differences between free and paid service plan
There is no difference in the functionality between the paid and the free plan. However, in the free plan you only have 500 Megabytes to store your transport content (as compared to 30 Gigabytes in the paid version). To check the used file quota click on the down arrow besides your user name on the overview screen and choose 'My File Quota'.

Check file quota
On the following screen you will see how much space has already been used. If you run out of space, it will not be possible anymore to create new transport requests. In this case you would have to manually delete transport requests you don't need anymore. Of course you can also switch to the paid version
😉

Used file quota
There is another difference between the free and the payable service plan of CTMS: transport request which are completely imported (in effect which are not waiting for import in any queue) are automatically deleted after 7 days (in the paid version after 30 days). This might help you to stay in the boundaries of your file quota.
Last not least there is no service level agreement (SLA) for the free version of CTMS and support happens via SAP Community only.
Switch to paid version
If you are satisfied with your tests using the free plan and would like to switch to the paid version of CTMS this is possible without losing any data. For that you need to add an entitlement for the 'standard (Application)' to your subaccount. Optionally you can also add the 'standard' service plan for programmatic access (if not already done above).

Add paid service plan
You now have an entitlement for the free and the standard application:

Free and standard entitlement
Now it is possible to update your subscription to CTMS from 'free' to 'standard'. For that go to your subaccount, open the 'Subscriptions and Instances' view and click on the three dots in the entry of 'Cloud Transport Management'. Here choose 'Update'.

Update subscription to CTMS
Switch the plan to 'standard' and click on 'Update Subscription'. Please note that it is
not possible to switch back to the free plan without data loss (you would have to delete the subscription and create it anew).

Switch to standard plan
After a few seconds the subscription has changed to 'standard', keeping your complete configuration and transport requests intact. This allows for a smooth transition to productive use of SAP Cloud Transport Management.