The Central Bank of Costa Rica has published, for the first time, the technical parameters needed to estimate the Costa Rican colón (CRC) zero-coupon curve, providing a more precise, arbitrage-free reference term structure for domestic interest rates. The parameters will be made available weekly each Monday before noon on the Bank’s Economic Indicators site under the interest-rate and sovereign yield-curve sections, with a historical time series starting on 2 February 2018. The approach derives the curve from observed market prices rather than internal rates of return, incorporates taxes and liquidity weightings, and applies optimisation techniques intended to improve stability and consistency in a low-liquidity market; the resulting curve can be used to compute discount factors, forward rates, par curves and foreign-exchange risk premia. A methodology paper and related webinar materials have also been published.