The British-born 22-year-old clocked four minutes 05.93 seconds over 1500m at the KBC Night of Athletics in Heusden-Zolder, Belgium, at the weekend.
She finished third behind Ethiopian Abebe Arigawi, a 4min 01.96sec winner, and Erin Donohue (USA), who took second with 4min 03.91sec.
Hamblin's time clipped .3sec off Hodgkinson's national record of 4min 06.23sec set in Melbourne in March 2000.
Hamblin, who gained New Zealand citizenship just prior to the world championships in Berlin last August, said afterwards that the fast time was surprising.
"The first lap was a bit messy, a lot of pushing and a lot of shoving. I sat towards the back and just had to believe I had the strength to come through. I started picking people off from about 600m," she said.
Now that she had dipped under 4min 06sec, Hamblin said she would be able to gain entry into the big races.
"Then you really mix it with the top girls - once you are in those races it is much easier to get pulled around to even faster times."
Hamblin has been competing in Europe in the lead-up to October's Commonwealth Games, where she has been selected in both 800m and 1500m.
Her form over the two-lapper has also been sharp, with a 2min 01.78sec win to her credit just a week ago in the Netherlands.
Hamblin's personal best, 2min 00.90sec, was set a year ago, and is closing in on Hodgkinson's national record set of 1min 58.25sec set at the Atlanta Olympics in July 1996.
