A ThruPlay is Meta’s measure of a video ad that someone actually watched: played to the end if the video is shorter than 15 seconds, or played for at least 15 seconds if it is longer. Cost per ThruPlay is your spend divided by that number.
How ThruPlay works
The rule depends on length. A 10-second Reel counts a ThruPlay only when someone sees all 10 seconds. A 90-second explainer counts one once someone has watched 15 seconds, even if they leave at second 16. That makes ThruPlay a measure of genuine viewing rather than a scroll past, but it does not mean the whole long video was seen.
ThruPlay appears in two places. As a metric, it is a column you can add to any Ads Manager report alongside impressions, reach and video plays at 25%, 50%, 75% and 100%. As a delivery choice, it is a performance goal you can pick for video campaigns under the awareness or engagement objectives. With that goal, Meta shows the ad to people it predicts will watch to the ThruPlay point, and you can choose to be charged per ThruPlay rather than per thousand impressions.
The alias “video completion rate” is used loosely. Strictly, completion rate is the share of plays that reached 100%. ThruPlay is the same as a completion only for videos under 15 seconds.
Why it matters
Short video is now how many UK brands introduce themselves on Facebook and Instagram. ThruPlay tells you whether a video holds people long enough to deliver its message, which a raw count of plays cannot. If a 20-second video has plenty of impressions and few ThruPlays, the opening is not doing its job; look at your hook rate and hold rate to see where people leave.
ThruPlay viewers are also an audience. You can build a video view audience of people who reached ThruPlay and show them a follow-up ad with an offer. For a local business or a service with a long decision time, a cheap ThruPlay campaign followed by retargeting is a sensible two-step approach.
Common mistakes
- Reporting ThruPlays as success. They show attention, not enquiries or sales. A video with a low cost per ThruPlay can still produce no business.
- Optimising for ThruPlay when you want conversions. Meta will find people who watch videos, who are not necessarily people who buy. Use a sales or leads objective for that.
- Comparing videos of different lengths. A 6-second clip is far easier to watch to the end than a 15-second one, so its cost per ThruPlay looks better without being a better ad.
- Saving the message for the end of a long video when most ThruPlays happen at 15 seconds.
- Mixing up ThruPlays with 3-second plays Which count almost any pause in the feed.
How to act on it
Add ThruPlays, cost per ThruPlay and the quartile columns to a saved Ads Manager view. When testing several videos, keep them within a few seconds of each other in length so the comparison is fair. Put the brand and core message inside the first 15 seconds, and treat anything after that as a bonus for the interested.
Use ThruPlay campaigns for reach and warm-up, then judge the whole plan by what the retargeting stage produces in leads or sales. Running that kind of two-stage video programme is part of my Facebook video, Reels and Stories ads service.