HBO’s ‘Harry Potter’ Budget Finally Has a Real Number, and It Beats ‘Game of Thrones’

Speculation about what HBO is spending on its wizarding world reboot has ranged from the plausible to the absurd, with figures as high as $100 million per episode circulating for over a year. Those numbers were always estimates built on little hard evidence. The ‘Harry Potter’ HBO series budget has now been given something closer to a factual foundation.

The source is unusually concrete. Because the show films in the UK, its production company must file annual accounts, and ‘Harry Potter’ is being made through a special purpose vehicle called Plum Jam Productions.

Those filings tell a clear story. Deadline reported that Plum Jam’s revenue hit £130.6 million, roughly $175 million, in 2025, the year Season 1 entered production at Warner Bros. Studios Leavesden, following £18.4 million in 2024 when development began.

Using the company’s earnings as a rough guide, the first season could average around £18.8 million, or $25.2 million, per episode. Taken together, the filings point to as much as £150 million, about $201 million, spent launching the project.

That places it in rarefied company. A source familiar with the adaptation confirmed the show will rank alongside the final season of ‘Game of Thrones’ and ‘The Last of Us’ among HBO’s most expensive productions.

First trailer for the ‘HARRY POTTER’ series. Releasing this Christmas on HBO. https://t.co/X5PPZ3ME46

— DiscussingFilm (@DiscussingFilm) March 25, 2026

For comparison, the ‘Game of Thrones’ finale season was widely reported at $15 million per episode, meaning this comfortably exceeds it. HBO declined to comment on the figures, which The Times of London first reported.

Deadline was careful to flag the limits of the data. Plum Jam has housed other productions in the past, including HBO’s ‘The Nevers’, when the company was known as Roundabout Productions, so its revenue may include unrelated income. The accounts also don’t capture everything. Filming wrapped in May 2026, meaning the 2025 figures cover only part of production, with post-production costs still to be added.

There’s a structural reason the early spending looks so high. A source said production costs are front-loaded because the lavish sets built at Leavesden were designed to serve all 7 planned seasons, one per book.

That should bring the average down over time. Those sets represent a one-time capital outlay rather than a recurring per-season expense, so future episodes are likely to land considerably lower. UK tax incentives may also reduce the net figure, a scheme that didn’t exist when the original 8 films were made.

New look at Professor Dumbledore, Professor Snape, and Professor McGonagall in HBO’s ‘HARRY POTTER’ series. https://t.co/gjXmJfnzel

— Pop Base (@PopBase) September 2, 2026

The comparison to Warner Bros.’ own franchise is striking. ‘Harry Potter and the Half-Blood Prince’ and both ‘Deathly Hallows’ films reportedly cost $250 million each, the most expensive entries, while the studio spent between $1.155 billion and $1.2 billion across all 8 movies.

The reported £147.4 million spent by the end of 2025, roughly $197.1 million, arrived halfway through production on a single season. If the total reaches $250 million across 8 episodes, that would average $31.25 million per installment. Season 1, titled ‘Harry Potter and the Philosopher’s Stone’, premieres on HBO Max on December 25 with 8 episodes. Francesca Gardiner serves as showrunner.

THE NEW HBO’s HARRY POTTER TRAILER IS HERE Releasing this Christmas on HBO https://t.co/OvCm0Lz4bL

— Wizarding World Direct (@WW_Direct) September 2, 2026

The cast is led by Dominic McLaughlin as Harry, Alastair Stout as Ron, and Arabella Stanton as Hermione, chosen from roughly 40,000 auditioning actors. They’re joined by John Lithgow as Dumbledore, Paapa Essiedu as Snape, Janet McTeer as McGonagall, Nick Frost as Hagrid, and Bel Powley and Daniel Rigby as the Dursleys. HBO renewed the show for a second season in May 2026, before a single episode aired, with ‘Chamber of Secrets’ already filming.

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