Lopez gets $1,762,500 under Wednesday's agreement, up from $515,000 last year. Outman received $675,000, an increase from $482,000.
Lopez was 6-3 with a 2.17 ERA for Houston last year and had just eight walks in 66 1/3 innings. The 29-year-old was acquired by Colorado on Dec. 4 for right-handers Alex White and Alex Gillingham.
The 28-year-old Outman, obtained from Oakland in January 2012, was 1-3 with an 8.19 ERA in seven starts and 20 relief appearances for the Rockies.
Both were eligible for arbitration for the first time.
Four Rockies remain in arbitration: right-hander Jhoulys Chacin, outfielders Tyler Colvin and Dexter Fowler and infielder Jonathan Herrera. They are set to swap proposed arbitration salaries with Colorado on Friday.