If you're running a business in Peru with dollar-denominated costs — imports, SaaS subscriptions, foreign suppliers — Friday's close is the number you need on your dashboard.
According to the Banco Central de Reserva del Perú (BCRP), the dollar closed the session of Friday, July 31 at S/ 3.3990, opening that same day at S/ 3.4000. The official closing rate is published on the website of the Superintendencia de Banca, Seguros y AFP (SBS).
Why the spread matters for founders
Every exchange transaction has two prices: the buy price (what a buyer pays to acquire the asset) and the sell price (what a seller accepts to part with it). The gap between those two figures is where margin gets quietly eaten. If you're converting soles to dollars to pay a vendor, you're always on the worse side of that spread.
The math is simple. A business converting S/ 100,000 to dollars at a 0.05-sol spread loses roughly $15 per thousand soles exchanged — real money if you're doing this weekly.
When to make your move
Timing is a lever most founders ignore. Financial institutions and exchange houses typically offer better rates between 9 a.m. and 1 p.m., Monday through Friday. Doing your conversions outside that window — or on a Saturday — often means accepting a wider spread and a less competitive rate.
For bootstrapped operators with thin margins, this is not a trivial detail. Locking in your weekly or monthly conversion during peak liquidity hours can protect one to two percentage points of purchasing power over a quarter.
The bigger picture
A stable exchange rate environment benefits free enterprise: it lowers the cost of planning, reduces hedging complexity for small businesses, and makes dollar-priced contracts more predictable. Peru's market-determined exchange rate, anchored by BCRP transparency, gives founders a reliable reference — something not every economy in the region can claim.
Watch the SBS site for the official daily close. Build it into your Friday cash report. Founders who track this weekly make better procurement decisions than those who check it only when a payment is due.



