Episode #1.1 - S1-E1
Continuity mistake: When David meets the Home Secretary for the first time outside her car, he is wearing a grey shirt. In the next scene (in the lobby) his shirt is white, before turning grey again later.
Bodyguard (2018)
1 continuity mistake in season 1
Starring: Tom Brooke, Claire-Louise Cordwell, Stuart Bowman, Vincent Franklin
Episode #1.6 - S1-E6
Factual error: When Commander Anne Sampson appears in her body armour she wears the rank insignia only worn by the Commissioner (a crown over a pip over crossed tipstaves in a wreath) instead of that worn by her own rank of Commander (crossed tipstaves in a wreath). She has apparently been promoted four ranks.
Episode #1.6 - S1-E6
Trivia: In the park where PS Budd is surrounded by armed tactical response officers, a careful observer would notice that the brand of ear protection devices the officers are wearing are Z-TAC, an airsoft brand.