United National Heavyweight Championship (Zero1)
The United National Heavyweight Championship is a professional wrestling title in the Japanese promotion Pro Wrestling Zero1. It is one of ZERO1's top two singles titles, along with the Zero1 World Heavyweight Championship. The UN title was created on January 31, 2004, when Masato Tanaka defeated Steve Corino in an Indian strap match, wrestling as Masa Tanaka. It was founded at a time when Zero1 was a member of the National Wrestling Alliance; since the two organizations' parting in late 2004, the NWA does not recognize or sanction it, though it retains the NWA initials. There have been a total of 26 recognized champions who have had a combined 32 official reigns. The title was revived by NWA Pro Wrestling in January 2011. NWA began recognizing title and sanctioning title matches in January 2011 after Zero1 was reinstated as a member of NWA. NWA stopped sanctioning the title after Zero1 left the NWA again in 2011.Title history
Combined reigns
As of ,.
| Rank | Wrestler | No. of
reigns | Combined
defenses | Combined days |
| 1 | | 1 | 2 | 937 |
| 2 | | 3 | 7 | 458 |
| 3 | | 2 | 8 | 379 |
| 4 | Towa Iwasaki | 1 | 3 | 314 |
| 5 | | 1 | 0 | 313 |
| 6 | Shogun Okamoto | 1 | 2 | 280 |
| 7 | | 1 | 2 | 275 |
| 8 | | 1 | 5 | 258 |
| 9 | | 1 | 1 | 257 |
| 10 | | 1 | 5 | 251 |
| 11 | | 1 | 3 | 250 |
| 12 | | 1 | 2 | 199 |
| 13 | | 1 | 3 | 190 |
| 14 | | 1 | 0 | 182 |
| 15 | Zeus | 1 | 0 | 170 |
| 16 | Kamikaze | 2 | 2 | 163 |
| 17 | Chris Vice † | 2 | 0 | + |
| 18 | Buffa | 1 | 1 | 133 |
| 19 | | 1 | 1 | 117 |
| 19 | | 2 | 1 | 117 |
| 21 | | 1 | 1 | 107 |
| 22 | | 1 | 0 | 72 |
| 23 | Sandy Beach | 1 | 0 | 47 |
| 24 | | 1 | 0 | 39 |
| 25 | | 1 | 0 | 30 |
| 26 | | 1 | 0 | 26 |
| 27 | | 1 | 0 | 2 |
