Short answer. It depends on how the drugs were seized. Where a search warrant is served, the inventory must be done at the place of the search. For warrantless seizures, it may be done at the nearest police station or the nearest office of the apprehending team, whichever is practicable.
What the law says
the physical inventory and photograph shall be conducted at the place where the search warrant is served; or at the nearest police station or at the nearest office of the apprehending officer/team, whichever is practicable, in case of warrantless seizures
RA 9165, Section 21 — Chain Of Custody. Read the full provision →
Two different rules for two kinds of seizure
Section 21 sets the place of inventory by how the drugs came into police hands. The text provides that the physical inventory and photograph shall be conducted at the place where the search warrant is served; or at the nearest police station or at the nearest office of the apprehending officer/team, whichever is practicable, in case of warrantless seizures. A search-warrant seizure is inventoried where the warrant is served — the premises searched. A warrantless seizure, such as one from a buy-bust or a search incident to a lawful arrest, may be inventoried at the nearest station or office.
Why a warrant fixes the place at the scene
When officers act on a search warrant they arrive prepared: the location is known in advance, and there is time to arrange for the required witnesses to be at the premises. The statute therefore holds them to inventorying on the spot, where the warrant is served, rather than moving the items first. Doing the count and photographs at the searched premises, in front of the accused and the witnesses, closes the earliest and most vulnerable gap in the chain of custody — the interval between seizure and the first written record of what was taken.
Warrantless seizures get a practical allowance
A buy-bust or a street arrest is unplanned, and doing a full inventory in a hostile or unsafe spot may be impossible. For those situations the law lets the inventory happen at the nearest police station or at the nearest office of the apprehending officer/team, whichever is practicable. The words that carry the weight are 'nearest' and 'practicable': the allowance is for the closest suitable place, not the team's home base across town, and moving the drugs further than necessary before the count is the kind of thing a later review will probe.
Getting the place wrong is not automatically fatal
As with the other requirements of the section, inventorying in the wrong place does not by itself void the seizure. The saving clause allows noncompliance under justifiable grounds, so long as the integrity and evidentiary value of the items are preserved. But the burden is on the prosecution to explain why the statutory place could not be used and to show the drugs were not tampered with along the way. For someone reviewing a seizure, the useful questions are where the inventory was actually done, why, and how far the items travelled before it happened.