Why Email Attachments Can Drive Up Dynamics 365 Storage Costs and How to Control Them

Picture a typical quarter-end. A Dynamics 365 administrator opens the Power Platform admin center to review capacity before the next licensing cycle. File capacity is nearing its limit, but no new application has been deployed and no major data import has taken place. Instead, storage has grown gradually as users track emails with attachments, embedded images, and forwarded threads in CRM. Now, the administrator must determine what can be moved or removed, what users still need, and whether additional capacity is necessary.

If this situation sounds familiar, this article explores why email attachments can drive up Dynamics 365 storage costs and what you can do to manage that growth

For a broader look at how document management apps can help free up CRM storage and manage attachments in the cloud, explore this MSDynamicsWorld white paper from Inogic.

This article examines where that storage accumulates, analyzes the financial impact of Dataverse capacity tiers, and outlines how solutions like Attach2Dynamics provide a structured, automated way to bring storage growth under control.

How Dataverse Capacity Works, and Where Email Attachments Fit

Dataverse capacity is shared across your whole organization and split into three types:

• Database capacity: structured data such as accounts, contacts, opportunities, and activity records.
• File capacity: file and image data, including attachments and notes.
• Log capacity: audit logs, plug-in trace logs, and similar data.

Attachments are stored in file capacity, which is also one of the smallest pools. Entitlements are added per license: a Power Apps per-user license, for example, contributes only 2 GB of file capacity to the tenant. Dynamics 365 applications carry their own defaults, so check the current figures for your licenses in Microsoft's Power Platform Licensing Guide.

This creates a mismatch. Entitlements grow with the number of licensed users, but attachments grow with the volume of email those users track, and attachments are rarely deleted. A team can stay within its license count and still outgrow its file allowance. When consumption exceeds what your licenses provide, you either clean up data or buy add-on capacity.

Running low on file capacity? Explore Attach2Dynamics to move email attachments out of Dataverse.

Why Email Attachments Drive CRM Storage Growth

Email is high volume by nature, and CRM adoption pushes it higher. Three things combine:

1. Every tracked email creates multiple records. Email activities are stored in the Dataverse database across several underlying tables. Microsoft's documentation notes that the email body is stored in the description column of the activity table, and that large email bodies can contribute noticeably to growth in the capacity that table consumes.

2. The same attachment is typically stored again with every email it travels in. Saving an attachment to an email creates an ActivityMimeAttachment record backed by a file blob, as described in Microsoft's documentation on email activity tables. Because each tracked reply and forward can carry its own copy, a single 5 MB proposal sent to 20 recipients across a sales cycle can quickly become hundreds of megabytes.

3. Notes add to the same pool. Files attached to Notes (the Annotation table) draw from the same file capacity, so the problem compounds when users attach documents in more than one place.

A practical effect: your database may look healthy while file capacity runs out. Industry write-ups on Dataverse costs consistently point to attachments (photos, receipts, PDFs) as the first thing to exhaust file capacity.

A Realistic Cost Example

The numbers below are illustrative, using Microsoft's list prices for add-on capacity: about $2 per GB per month for file storage and $40 for database storage. Replace them with your own figures from the capacity report.

Assume a team of 100 sales and service users, each sending or receiving about 10 tracked emails per day with attachments, averaging 1 MB of attachment data per email:

• Daily: 100 users x 10 emails x 1 MB = about 1 GB per day
• Annual: about 250 GB (working days)
• Over three years: about 750 GB

If that 750 GB were covered by add-on file capacity at $2 per GB per month, the annual run cost at that point is 750 x $24 = $18,000 per year, and it keeps growing every year, because attachments are rarely deleted. If any part of that growth lands in database capacity at $40 per GB per month, the same volume costs 20 times more.

The same data in SharePoint or Azure Blob Storage is priced by Microsoft Azure or your Microsoft 365 plan at a small fraction of Dataverse rates. See the current Azure Blob Storage pricing page for your region, and your Microsoft 365 plan for SharePoint storage allowances.

How to Diagnose Where Your Storage Is Going

1. Open the Power Platform admin center and go to Licensing > Dataverse (labelled Resources > Capacity in some tenants).
2. Review usage by environment and by capacity type (database, file, log).
3. Open the environment's table-level view and look at the largest tables. Typical offenders are Email (activity), Attachment (ActivityMimeAttachment), Note (Annotation), and audit logs.
4. Flag any environment above about 70% file utilization. Capacity warnings arrive late, and add-on purchases take time.
5. Compare against your entitlement: licenses x per-license capacity, plus tenant defaults.

What Are Your Options for Reducing Email Storage?

Option 1: Delete and retain less

Bulk delete jobs, retention rules, and policies on tracked email remove old data. This works for test and development environments and for emails with no business value. It is less suitable for production, where attachments often have legal, contractual, or customer-service value.

Option 2: Buy add-on capacity

Organizations can purchase additional database, file, or log capacity from Microsoft to cover usage above what their licenses include. This is the fastest fix and requires no change to how users work, but the cost is billed monthly and grows as attachments accumulate. It treats the symptom, not the cause.

 Option 3: Use native SharePoint integration

Dynamics 365 supports SharePoint document management for records. This is a good fit for documents that users deliberately upload to a record. It does not by default address the stream of attachments that arrive through email tracking.

Option 4: Offload attachments automatically to SharePoint or Azure Blob Storage

An automated approach moves attachments out of Dataverse as they arrive (or in bulk for historical data), stores them in SharePoint or Azure Blob Storage, and keeps them accessible from the CRM record. Files stored in SharePoint do not consume Dataverse file capacity, so the saving is immediate.

Attach2Dynamics moves email and note attachments to SharePoint, Azure Blob Storage, or Dropbox while keeping them accessible from the CRM record. Ready to try offloading? Get Attach2Dynamics on Microsoft Marketplace.

How to Prevent Email Storage Growth

• Limit what gets tracked. Use tracking rules so only emails relevant to CRM records are saved, not every message.
• Cap attachment size. Set a maximum file size and block file types you do not need in system settings.
• Watch inline images. Signature logos and banners are often saved as attachments with every tracked email, so standardize or remove them.
• Review capacity monthly. Check the capacity report regularly instead of waiting for a warning.

Conclusion

 Email will keep growing, and so will the attachments that ride along with it. Deleting data is rarely an option for business-critical attachments, and buying more capacity only increases recurring cost. The sustainable answer is to keep transactional CRM data in Dataverse, keep files in storage built for files, and make sure users never notice the difference.

To try Attach2Dynamics free for 15 days or request a demo, contact the Inogic team at [email protected] or visit www.inogic.com.

FAQs

How do I check Dataverse storage usage in Dynamics 365?

Open the Power Platform admin center, go to Licensing > Dataverse, and review usage by environment and by capacity type (database, file, and log).

Do email attachments count toward Dataverse storage?

Yes. Attachments and notes are stored as file blobs and count toward Dataverse file capacity.

Does moving files to SharePoint reduce Dataverse storage?

Yes. Files stored in SharePoint do not consume Dataverse file capacity.

Can existing attachments be moved in bulk?

Yes. Bulk migration tools, including Attach2Dynamics, can move attachments that are already in Dynamics 365 and route new ones to external storage as they arrive.

Can users still open files after they are moved?

Yes. Migrated attachments stay accessible from within the CRM, whether they are stored in SharePoint, Azure Blob Storage, or Dropbox.