The Red Bull Racing Formula 1 team shelled out more than $425 million over the course of the 2019 season.
It netted three wins over the course of the campaign and finish third in the constructors' championship.
The 2019 season was Red Bull's first with factory Honda engines, having previously been paying for customer Renault units.
It's a significant drop in expenditure from 2018, during which it spent $550 million (£304.9 million).
Last year's championship winners, Mercedes, spent close to $600 million according to reports revealed last month.
Costs for both teams will need to be drastically slashed ahead of 2021 as financial regulations introduce a budget cap of USD 145 million – about $200 million by the current exchange rate.
Red Bull currently sits second in the 2020 championship behind Mercedes, which is on course to win an unprecedented seventh consecutive constructors' title.
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