The first production version, designated P3V-1, first flew 15 April 1961, but by the time the first deliveries were made in 1962, the unified designation system made this the P-3.
Over the years, many variants have been developed.
Variants
- P-3A: original production version, 157 built
- P-3A (CS): four with better radar, for US Customs[?]
- EP-3A: seven modified for electronic reconnaissance testing
- NP-3A: three modified for US Naval Research Laboratory[?]
- RP-3A: two modified for scientific uses, for Oceanographic Development Squadron[?] at NAS Patuxent River[?]
- TP-3A: 12 modified for training, ASW gear removed
- UP-3A: 38 used as utility transports, ASW gear removed
- VP-3A: three WP-3As and two P-3As converted into VIP, staff transports
- WP-3A: four converted for weather reconnaissance
- P-3B
- EP-3B
- NP-3B
- P-3C
- Update I
- Update II
- Update II.5
- Update III
- Update IV
- EP-3C
- NP-3C
- RP-3C
- UP-3C
- RP-3D
- WP-3D
- EP-3E Aries
- EP-3E Aries II
- NP-3E
- P-3F
- P-3G
- P-3H
- P-3K: five delivered to New Zealand
- P-3N
- P-3P
- P-3W
- P-3AEW&C
- CP-140 Aurora
- CP-140A Arcturus