List of AC Transit Routes - Route Summary

Route Summary

AC Transit bus routes are arranged in six categories (five numbered, one lettered). Since its inception in 1960, AC Transit has used both numbers and letters to distinguish routes. Many Transbay rail lines were inherited from the Key System and converted to bus routes, and AC Transit continued to use letters to identify the routes. Many Transbay routes continue to follow the original Key System routings to some degree. The number and letter ranges listed below do not mean that all numbers or letters with a range are in use.

Numbered routes operate within the East Bay:

• 1 to 99 primarily serve the northern part of Alameda County and all of Contra Costa County.
• 200 to 299 serve the southern part of Alameda County and Milpitas.
• 300 to 399 serve combined portions of other bus lines, usually only at certain times of day or certain days of the week.
• 600 to 699 operate on school days only.
• 800 to 899 are part of the All Nighter network, which provides bus service during owl hours and at times when BART is not operating.

One- and two-digit route numbers are sometimes used as a "base" number for three-digit route numbers. For example, Route 339 is "based" on Route 39.

Lettered routes (A to Z) provide Transbay service (i.e., service across a bridge) between the East Bay and San Francisco, San Mateo, and Santa Clara Counties.

Suffixes (also lettered) are used on some local and Transbay routes to distinguish different routings. Currently, A, B, C, L, M, R, S, and X are used. Some suffixes have special meanings:

• C - Denotes Combined service on Transbay routes, where portions of two or more routes are combined into a single route during the PM commute period. Used on Routes LC and NXC.
• L - Denotes Limited stop service, where not all local stops are served. Used on Routes 58L and NL.
• R - Denotes Rapid service, which is similar to limited stop service. Used on Routes 1R and 72R.
• X - Denotes Express service, where portions of the main route as skipped entirely. Used on Routes NX, NX1, NX2, NX3, NX4, and OX.

Supplemental numerical suffixes are used to differentiate route variations for lines that already use a lettered suffix. This is the case with the NX lines listed above.

Note: Routes listed below are current as of December 18, 2011.