Todd McCarthy in The Hollywood Reporter:
It ends well. After eight films in 10 years and a cumulative global box-office take of more than $6.3 billion, the most successful franchise in the history of movies comes to an obligatory -- and quite satisfying -- conclusion in Harry Potter and the Deathly Hallows Part 2. Fully justifying the decision, once thought purely mercenary, of splitting J.K. Rowling's final book into two parts, this is an exciting and, to put it mildly, massively eventful finale that will grip and greatly please anyone who has been at all a fan of the series up to now. If ever there was a sure thing commercially, this stout farewell is it.
Justin Chang in Variety:
It's taken 10 years and nearly 20 hours of screen time for J.K. Rowling's towering fantasy saga to reach its cinematic conclusion. Yet as the final incantation is spoken and the curtain falls on the highest-grossing franchise in movie history, more than a few viewers may be left wondering: Why the rush? The series' shortest entry at 131 minutes, "Harry Potter and the Deathly Hallows: Part 2" surges ahead with tremendous urgency, superb spectacle and powerful, even overwhelming emotion, only to falter with a hasty sendoff that seems to buckle under the weight of audience expectations. Tears will be shed as fans bid farewell to Hogwarts, but catharsis remains just out of reach.
Perhaps the greatest triumph of this final film is its ability to overcome the deficiencies of J K Rowling’s writing. In the last Harry Potter volume, she failed singularly to muster the epic feel needed; as a result, on the page, the concluding battle at Hogwarts was a damp squib. But Yates here transmutes it into a genuinely terrifying spectacle, as bloodied students fight desperately against a horde of screaming black-robed Death Eaters.
The eighth and final film in the Harry Potter franchise is where good and evil are told what's what and the central mystery is revealed. It all comes together with a spectacular battle for Hogwarts, a curiously Christ-like resolution for Harry, and a final swoop over the newly restored St Pancras Hotel as we return to where it all began: King's Cross station.