At the beginning of the film a newspaper article talks about a muggle family being dead but the timing and number killed are not known, so will not be included. Also Hedwig dies in the film, but is a bird so will not be counted.
9:16 Burbage is killed by Voldemort.
22:31 Moody is confirmed dead.
35:37 It is confirmed that the ministry of magic has fallen and the minister was killed.
35:55 A partygoer at the wedding is killed.
1:13:37 A radio transmission confirms a list of names killed that totals 19 names.
1:31:27 It is revealed that Nagini is impersonating an old lady that lived in the house the group is in and is dead in another room.
2:11:12 Dobby is killed by a dagger thrown by Bellatrix
Total: 25