The moving-average cost method for crypto KESt in Austria

What the moving average is

The gleitender Durchschnittspreis is a running average cost per asset. Every time a user acquires more of a given crypto, you blend the new purchase into a fresh average across their whole holding of it. When they later dispose, the gain is measured against that average, not against any specific lot. It's the same logic Austria applies to securities.

Why it's harder than FIFO

FIFO just needs an ordered list of purchases; you match disposals against the oldest first. A moving average has to be recomputed on every acquisition, in the right order, across every venue and wallet the user holds that asset on. Miss one inbound transaction, or process events out of order, and the average is wrong, which means the withheld KESt is wrong from that point forward.

The consolidation problem

The average is per asset per user, but users don't keep an asset in one place. A single user's ETH might sit across your platform and several external wallets. To compute a correct average you need a consolidated, deduplicated view of every acquisition, which is a data problem before it's a tax one.

Getting it right at source

Because withholding happens at the moment of disposal and is final under Endbesteuerung, there's no annual reconciliation to catch an error later. The average has to be right in real time. Our tax withholding solution maintains the moving-average basis per user per asset across all their sources, so the gain you withhold on is the gain Austria actually recognises. It shares a data layer with our CARF and DAC8 reporting, and the Austrian Federal Ministry of Finance publishes the underlying rules.