Why the rule exists
The official Mexican tequila standard requires 100% agave tequila to be bottled by the authorised producer within the denomination of origin.
This protects the category and keeps control of the product through production and bottling.
What can be exported in bulk
The tequila category that uses at least 51% blue agave sugars can be exported in bulk and bottled outside the protected territory under the correct arrangements.
This is normally called mixto in the trade, although the bottle may simply say tequila.
Can you get close to 100%?
Yes. A mixto does not have to stop at 51% agave. It can be made with a much higher agave percentage, including up to 99%, while remaining within the category that can be exported in bulk.
That can be a useful option for a UK brand that wants strong agave character and local production.
Do not let the label mislead you
If someone offers genuine 100% agave tequila for bulk export and UK bottling, ask them to explain the legal route in writing.
For a compliant project, the product category, paperwork, production plan and label all need to tell the same story.