How it's calculated
Official: $ 500.000,00 ÷ 38,1648 (Argentine pesos by Uruguayan peso, dolarapi.com, 13/11/2026) = 13.101 UYU. It's the bank reference; in a exchange house you're gonna get a little less by the margin.
Blue cross: If you have Argentine pesos in cash, the usual thing is to buy dollars from the blue ($ 1.570,00) and change them in Uruguay; That's equal to 38,1648 Argentine pesos by Uruguayan peso, i.e. 13.101 UYU.
With a card: the consumption is charged to card dollar ($ 2.041,00), so give less: a few 10.078 UYU. If you pay the summary with your own dollars, there's no advance tax collection.
A month ago, with $ 500.000 You were buying. 13.288 UYU to the official rate.