Japanese customs are precise, procedural and, if the documentation is precise too, fast. Nothing about them is designed to be difficult. What they do not tolerate is ambiguity, and the single most expensive thing you can write on a Japanese invoice is a generic goods description. “Machine parts” invites a question; a description that supports the tariff line does not.
The second recurring issue is valuation on non-sale movements. Samples, returns, qualification pieces and demonstration items have a value even when there is no sale, and “no commercial value” written on its own is not a valuation. A proforma invoice with a defensible basis is what keeps a sample moving.
Temporary admission matters more here than most places because so much of the traffic is equipment going out to be tested or demonstrated and coming back. An ATA Carnet where the category fits removes the duty and deposit question entirely; importing outright instead creates a cost and an argument that were both avoidable.
Consignee details are the third. The registered name and address as they appear on the consignee's own records have to match the paperwork exactly. A near match is a mismatch, and in Japan that costs time rather than being waved through.


