Monthly tracked users (MTUs) billing guide

  • Updated

As an events-based product, Amplitude has always used the number of events as the basis of customer billing. However, this is not always the most effective approach for certain types of customers, especially smaller companies trying to ramp up an analytics program for the first time. For that reason, Amplitude now offers some customers on Growth and Enterprise plans the option to use monthly tracked users (MTUs) for billing purposes.

An MTU is a unique user who triggers one or more events in a project within a calendar month. No matter how many events a user triggers each month in a project, Amplitude will count them as a single MTU. However, if the same user exists in multiple projects, it will be counted as a separate MTU in each project. 

An MTU can be either an anonymous user (which Amplitude will track via device ID), or an identified user (tracked by user ID). Amplitude will track any anonymous users as distinct MTUs, even if they have previously visited while logged in. If an anonymous user subsequently logs into the site, all events triggered by the user while they were anonymous will be merged under their user ID, and will count as a single MTU.

Amplitude calculates MTU usage daily, with one additional, final calculation after the end of the calendar month to accommodate any late-arriving events. At that point, the MTU count is no longer updated to reflect subsequent user merges caused by identify calls on anonymous users. 

NOTE: Your MTU count will not increase due to user mapping, identify calls, or group identifies.

MTUs are available for customers on the following plans:

  • Free Starter plan: up to 50K MTUs
  • Scholarship plan: up to 200K MTUs
  • Growth and Enterprise plans: up to 1MM MTUs

In order to use MTUs instead of events for billing, you must have fewer than 1 million MTUs. If your MTUs exceed this limit, but you still want MTU pricing, please contact your account team.

Estimate your MTUs

If you haven't implemented tracking yet, you can use your monthly active user (MAU) count to estimate your current MTU usage. These counts should be similar, assuming they account for anonymous visitors identically.

View and track your MTU usage

To view your MTU usage, navigate to Settings > General. MTU statistics will be visible in their own panel.


NOTE: MTU counts are not available for every plan type.

In some rare cases, a single user may be counted multiple times when totaling MTUs. This can happen when a user is logged in, but then later opens the app anonymously on a different device or platform. Because there is no way to connect these two users, they will register as distinct MTUs. It can also happen if a user has two unlinked user IDs and uses both of them in a single month.

There are also instances where a user’s actions can result in a reduced MTU count. If a user interacts with your app anonymously and then later logs into their account on that same device, the anonymous usage will be merged with the logged-in usage, resulting in a single MTU.

If you believe there is an error in your MTU count, please contact Amplitude support.

Monthly tracked users FAQs

What happens if I go over my monthly MTU limit?

Exceeding your monthly prepaid data limit will result in charges for all excess MTUs sent. Amplitude will determine whether any overage fees are owed based on your MTU volume calculated on the last day of each calendar month. Amplitude will alert you when you are approaching your limit so you can take steps to avoid exceeding it.

If you're a non-paying customer, your account will be blocked once you've exceed your monthly limit three times. You will no longer be able to access any of your charts and dashboards (you will still have access to certain admin functions, like the User API, so you can meet your compliance obligations). Data you send to Amplitude up to your limit will continue to be ingested; however, data past the limit will not be ingested. If you continue to exceed your monthly limit without upgrading to a paid plan, your account will be deleted six months after it was first blocked.

What does it mean if I see spikes in my MTUs?

Large and sudden increases in MTUs are almost always tied to spikes in usage of your product. If your company recently launched a new marketing campaign, a significant product update, or a change to your instrumentation, that may be the most likely explanation.

MTUs may also increase unexpectedly when you add new event sources that result in either more users, or more events for users active in third-party tools but not necessarily in your product (for example, adding an email platform as a data source).

When backdated events for previous months are added, Amplitude will add one MTU for each month in which a distinct user appears.

If you believe your MTUs have spiked in error, please contact Amplitude support.

Why is my MTU count different from that provided by other tools?

No two tools work exactly the same way, or under the exact same conditions. Most ingest and process data differently, which will naturally generate different results. Additionally, your MTU count could differ from the results generated by running a query of user count within Amplitude due to the way MTUs are calculated.

How do MTUs work across projects?

MTUs are tracked on a per-project basis. When users overlap between projects, MTUs will be the sum of usage within each project. This means that any users who are active in two different projects—even under the same user ID—will be counted once for each project, contributing two MTUs to your overall total.

What if I need to backfill event data into Amplitude?

MTU usage calculations are based on the month an event is added to Amplitude. If you were to backfill data into previous months in February, for example, Amplitude will count all this backfilled usage against February’s MTU quota.

Similarly, determining whether a user is unique or not also hinges on the month the event was triggered. For example, if Amplitude records three events for a single user, with one dated today, a second dated one month ago, and a third dated two months ago, the count will be 3 unique MTUs and the usage will be counted in this month.

Because of this, backfilling data is a common cause of spikes in MTU usage.