All assignees
800 prefixes in 303 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 303-900 | GEORGETOWN | 6118 | 2007-01-10 | Yes |
| 303-901 | DENVER | 6529 | — | Yes |
| 303-902 | DENVER | 6567 | — | — |
| 303-903 | DENVER | 6567 | — | — |
| 303-904 | DENVER | 9636 | — | — |
| 303-905 | DENVER | 6567 | — | — |
| 303-906 | DENVER | 6567 | — | — |
| 303-907 | DENVER | 6567 | — | — |
| 303-908 | DENVER | 6567 | — | — |
| 303-909 | DENVER | 6567 | — | — |
| 303-910 | DENVER | 6567 | — | — |
| 303-911 | XXXXXXXXXX | MULT | — | — |
| 303-912 | DENVER | 6567 | — | — |
| 303-913 | DENVER | 6567 | — | — |
| 303-914 | DENVER | 9636 | — | — |
| 303-915 | DENVER | 6567 | — | — |
| 303-916 | DENVER | 6567 | — | — |
| 303-917 | DENVER | 6567 | — | Yes |
| 303-918 | DENVER | 6567 | — | — |
| 303-919 | DENVER | 6567 | — | — |
| 303-920 | DENVER | 9636 | — | — |
| 303-921 | DENVER | 6567 | — | — |
| 303-922 | DENVER | 9636 | — | — |
| 303-923 | DENVER | 6118 | — | Yes |
| 303-924 | DENVER | 9636 | — | — |
| 303-925 | DENVER | 9636 | — | — |
| 303-926 | DENVER | 9636 | — | — |
| 303-927 | DENVER | 7378 | — | Yes |
| 303-928 | DENVER | 7229 | — | Yes |
| 303-929 | DENVER | 6567 | — | — |
| 303-930 | DENVER | 9636 | — | — |
| 303-931 | DENVER | 6529 | — | — |
| 303-932 | DENVER | 9636 | — | — |
| 303-933 | DENVER | 9636 | — | — |
| 303-934 | DENVER | 9636 | — | — |
| 303-935 | DENVER | 9636 | — | — |
| 303-936 | DENVER | 9636 | — | — |
| 303-937 | DENVER | 9636 | — | — |
| 303-938 | DENVER | 9636 | — | — |
| 303-939 | DENVER | 9636 | — | — |
| 303-940 | DENVER | 9636 | — | — |
| 303-941 | DENVER | 6567 | — | — |
| 303-942 | DENVER | 7378 | — | Yes |
| 303-943 | DENVER | 622J | 2021-09-09 | Yes |
| 303-944 | DENVER | 6529 | — | Yes |
| 303-945 | DENVER | 318J | — | Yes |
| 303-946 | DENVER | 6529 | — | Yes |
| 303-947 | DENVER | 6567 | — | — |
| 303-948 | DENVER | 9636 | — | — |
| 303-949 | DENVER | 6529 | — | Yes |
| 303-950 | — | — | ||
| 303-951 | DENVER | 6118 | — | Yes |
| 303-952 | DENVER | 6118 | — | Yes |
| 303-953 | DENVER | 6118 | — | Yes |
| 303-954 | DENVER | 6118 | — | Yes |
| 303-955 | DENVER | 6118 | — | Yes |
| 303-956 | FORTLUPTON | 6010 | — | — |
| 303-957 | DENVER | 6118 | — | Yes |
| 303-958 | — | — | ||
| 303-959 | — | — | ||
| 303-960 | DENVER | 6529 | — | — |
| 303-961 | DENVER | 6529 | — | Yes |
| 303-962 | DENVER | 026D | — | Yes |
| 303-963 | DENVER | 6118 | — | Yes |
| 303-964 | DENVER | 9636 | — | — |
| 303-965 | DENVER | 9636 | — | — |
| 303-966 | DENVER | 9636 | — | — |
| 303-967 | DENVER | 9636 | — | Yes |
| 303-968 | DENVER | 7229 | — | Yes |
| 303-969 | DENVER | 9636 | — | — |
| 303-970 | DECKERS | 026D | 2022-03-31 | Yes |
| 303-971 | DENVER | 9636 | — | — |
| 303-972 | DENVER | 9636 | — | — |
| 303-973 | DENVER | 9636 | — | — |
| 303-974 | DENVER | 6118 | — | Yes |
| 303-975 | DENVER | 9636 | — | Yes |
| 303-976 | — | — | ||
| 303-977 | DENVER | 9636 | — | — |
| 303-978 | DENVER | 9636 | — | — |
| 303-979 | DENVER | 9636 | — | — |
| 303-980 | DENVER | 9636 | — | — |
| 303-981 | DENVER | 6567 | — | — |
| 303-982 | DENVER | 9636 | — | — |
| 303-983 | — | — | ||
| 303-984 | DENVER | 9636 | — | — |
| 303-985 | DENVER | 9636 | — | — |
| 303-986 | DENVER | 9636 | — | — |
| 303-987 | DENVER | 9636 | — | — |
| 303-988 | DENVER | 9636 | — | — |
| 303-989 | DENVER | 9636 | — | — |
| 303-990 | FORTLUPTON | 6529 | 2006-05-16 | Yes |
| 303-991 | DENVER | 7229 | — | — |
| 303-992 | DENVER | 9636 | — | — |
| 303-993 | DENVER | 026D | 2007-03-27 | Yes |
| 303-994 | DENVER | 6529 | — | Yes |
| 303-995 | DENVER | 6529 | — | Yes |
| 303-996 | DENVER | 3467 | — | — |
| 303-997 | DENVER | 318J | — | Yes |
| 303-998 | DENVER | 9636 | — | — |
| 303-999 | DENVER | 318J | 2007-08-24 | Yes |
These are initial assignees from NANPA CO-code records — because of number portability, the current serving carrier of individual numbers may differ. Bulk export requires a membership.