Part of this road was once NJ 6N. A small portion of the road remains under state control as NJ 62.
| Mile | Street Name | Feature (South to North) |
| 0.00 | CR 646 BEGINS, Little Falls Twp | |
| 0.00 | Union Ave | (Railroad Ave] |
| 0.16 | Union Ave | Main St, CR 631 {signal} |
| 0.22 | Union Ave | Passaic River {bridge} |
| 0.22 | Entering Wayne Twp | |
| 0.35 | Union Blvd | Inlet Passaic River {bridge} |
| 0.35 | Entering Totowa Boro | |
| 0.38 | Union Blvd | [Riverview Dr, CR 640] {signal} |
| 0.99 | Next 0.47 mile co-signed with NJ 62 | |
| 0.99 | Union Blvd | Pellington Blvd, US 46 {overpass} |
| 1.14 | Union Blvd | (Furler St) [Lackawanna Ave, CR 632] {signal} |
| 1.22 | Union Blvd | Lackawanna Railroad spur {overpass} |
| 1.27 | Union Blvd | Bergen-Passaic Expwy, I-80 {overpass} |
| 1.66 | Union Blvd | Bogert St {signal} |
| 1.85 | Union Blvd | (Crews St) {signal} |
| 2.15 | Union Blvd | Totowa Rd, CR 644 {signal} |
| 2.56 | Union Blvd | Lincoln Ave {signal} |
| 2.86 | Entering Paterson City | |
| 3.25 | Union Ave | Richmond Ave {signal} |
| 3.28 | Union Ave | Oldham Brook {bridge} |
| 3.40 | Union Ave | Sherwood Ave {signal} |
| 3.55 | Union Ave | Preakness Ave, CR 666 {signal} |
| 3.75 | Union Ave | Wayne Ave {signal} |
| 4.18 | Union Ave | West Broadway, CR 673 {signal} |
| 4.18 | CR 646 ENDS, Paterson City | |