HBO’s Harry Potter Series Budget Revealed: Filings Point to About $25 Million Per Episode

HBO’s Harry Potter series is on course to rank among the most expensive shows the network has made, according to accounts filed in the UK. The first season could average about £18.8 million ($25.2 million) per episode, Deadline reports.

The figures come from Plum Jam Productions, the HBO-owned company producing the show in the UK. Its filings with Companies House, first reported by The Times, show spending of £147.4 million ($197 million) by the end of 2025. Filming began in July 2025 and did not wrap until May 2026, so the final cost for season one will be higher.

Deadline calculated its per-episode estimate from the company’s reported 2025 revenue of £130.6 million ($175 million). That would put the series in the same bracket as the final season of Game of Thrones, widely reported at $15 million an episode, and The Last of Us. Another report put the season at as much as £150 million ($201 million).

A source told Deadline that costs are front-loaded because of the large sets built at Warner Bros. Studios Leavesden, which means average budgets for later seasons are likely to drop. For comparison, the most expensive of the original films, Harry Potter and the Half-Blood Prince, reportedly cost $250 million, and the eight films together cost roughly $1.2 billion.

HBO has not confirmed a budget. The $100 million per episode figure that has circulated online does not match the filings, which work out to roughly $24.5 million an episode if all spending to date went to season one’s eight episodes. Harry Potter and the Philosopher’s Stone premieres on HBO Max on December 25, and season two is already in production.