Discrepancies between your internal reporting and Sovrn's numbers are common in programmatic advertising — and in most cases, they're explainable. Before escalating to support, work through the checkpoints below to narrow down the cause.
Reporting setup
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Date ranges match. Confirm you're comparing the same date range in both systems, including timezone. Sovrn reports in UTC.
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You're using the right ad format filter. In the Sovrn Platform, CTV and mobile app traffic won't appear unless you explicitly apply the Ad Format filter. If you run app inventory, impressions and revenue from those placements are excluded from unfiltered views.
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You're comparing the right metrics. Sovrn reports on paid impressions — impressions that resulted in a billable event. Your ad server may be counting ad requests, filled impressions, or rendered impressions, which are all different numbers.
Impression tracking method
The tracking method configured for your inventory directly affects when Sovrn logs an impression. Misalignment here is one of the most common sources of discrepancy.
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Ensure alignment on impression tracking methodology. Sovrn supports ADM or BURL for impression tracking across web and mobile app display. Sovrn will default to using ADM unless otherwise requested by the publisher.
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You understand how bill on render affects your count. For mobile app display inventory, Sovrn logs impressions on a bill-on-render basis when certain demand partners win the auction (DV360, Magnite, PubMatic, Equativ, and OpenX). In this model, an impression is only counted when at least one pixel of the creative is viewable for any amount of time. If a significant share of your inventory isn't in view, your ad server's impression count will be higher than Sovrn's. See Ad Exchange: Fall 2025 Impression Tracking Update for full details.
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Video impressions are tracked via VAST. For all video inventory, Sovrn fires its tracking pixel inside the VAST
<Impression>event. If your player or ad server fires its own impression counter at a different point (e.g., on ad load rather than video start), you'll see a count difference.
Auction and fill dynamics
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Unfilled and passback requests are excluded. Sovrn only reports on impressions it won and served. Requests that resulted in no fill, a passback, or a timeout won't appear in Sovrn reporting — but your ad server may still be counting them.
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Invalid traffic (IVT) has been filtered out. Sovrn filters invalid traffic before counting impressions. If your ad server counts all served impressions regardless of validity, the numbers won't align.
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Header bidding timeouts. If your
tmaxsetting is aggressive, Sovrn bids may time out before returning. Those requests won't appear in Sovrn reporting. For CTV and mobile app, Sovrn enforces a 500mstmaxceiling.
Revenue-specific checkpoints
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Currency and exchange rates. If any part of your stack reports in a non-USD currency, confirm you're applying the same exchange rate across both systems.
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CPM calculation methodology. Confirm your ad server and Sovrn are calculating CPM the same way (revenue ÷ impressions × 1000). A difference in the impression count used as the denominator will produce a CPM discrepancy even when underlying revenue matches.
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Clawbacks and adjustments. Sovrn may apply post-auction adjustments for IVT or billing disputes from demand partners. These will affect your final reported revenue and may not be visible in real time.
If you've worked through the list above and still can't account for the discrepancy, reach out to support with the following details to speed up the investigation: the date range affected, the inventory type (web display, mobile app, video, CTV), the tracking method in use, and daily reporting from your system for the time period of the discrepancy with revenue and impressions. The more granular the data the better so Sovrn can investigate accordingly on our side.
Questions? Concerns? Our team would be more than happy to help. Reach out to our Support Team here.