This is the "Streaming Decade," Roku (ROKU 1.58%) CEO Anthony Wood has said. The world is moving to streaming as consumers cut out traditional pay TV, with eMarketer estimating that less than half of U.S. households will subscribe to traditional pay-TV services by the end of 2024. As the leading streaming-TV platform, Roku is obviously well positioned to benefit.

The massive tailwinds behind streaming TV, combined with Roku's strong positioning in the nascent category, continued to fuel the tech company's business in Q4. On Wednesday morning, Roku announced record active accounts and an acceleration in streaming hours on its platform for the final quarter of 2020.

A woman eating popcorn while sitting on a couch

Image source: Getty Images.

Impressive Q4 user metrics

Roku racked up 51.2 million active accounts by the end of Q4, the company announced on Wednesday morning. This translates to 5.2 million new accounts in Q4 alone, an acceleration from the 3 million accounts the company added in Q3. Further, it puts total new active accounts in 2020 at 14.3 million -- meaningfully higher than the 9.8 million accounts the company added in 2019.

Roku's recent growth in streaming hours is arguably even more notable. Users streamed 17 billion hours of content in Q4, bringing total 2020 streaming hours in 2020 to 58.7 billion. This translates to 55% year-over-year growth for both Q4 and the full year. The year-over-year growth in streaming hours marked a slight acceleration from 54% growth in Q3 -- a period that was likely aided by many consumers spending more time at home than usual as they reduce in-person contact to help mitigate the spread of COVID-19.

A strategic bet on CTV

While Roku investors will have to wait until the company releases its official fourth-quarter results to see how this strong user growth impacted its financials, it wouldn't be surprising to see the company's platform business post another quarter of 70%-plus year-over-year growth in the segment.

With its platform business (accounting for 71% of total revenue) mainly representing Roku's share of subscriptions and advertisements on its platform, the company is uniquely positioned to benefit from the success of nearly all participating stakeholders in the streaming-TV revolution.

A bar chart with an arrow highlighting a growth trend.

Image source: Getty Images.

"The world is moving to streaming and we look forward to continuing to help viewers, advertisers, content publishers, and TV manufacturers succeed in the Streaming Decade," said Wood in the company's Wednesday morning press release.

Roku management is particularly excited about the opportunity to grab market share from traditional TV marketing budgets. Management asserted in its third-quarter shareholder letter that it saw "clear evidence that marketers accelerated their shift out of traditional TV and into TV streaming" -- a trend that led to an acceleration in monetized video ad impressions on its platform.

Roku investors will get a more detailed look at the company's fourth-quarter results in early February, when Roku typically reports earnings for the holiday quarter. Nevertheless, these preliminary user metrics bode well for the streaming-TV company's continued momentum.