[tz] Philippine Standard Time

Paul Eggert eggert at cs.ucla.edu
Tue Jun 19 15:50:02 UTC 2018

Paul Goyette wrote:
> Hmmm, the silence here is deafening!

Sorry, I've been busy with TZif stuff when I had time for tz-related things.

When I looked into this a couple of years ago, I looked for instances of "PHST" 
for Philippine Standard Time, as that is what tzdb used. I found few so PHST 
didn't make the cut. I didn't know about PST being part of recent Philippine law.

I just now checked more carefully, and found several instances of PST meaning 
Philippine Standard Time in reliable English-language sources. PST is the 
abbreviation tzdb used in releases 93g through 96j, and (as you reported) has 
been in Philippines law since 2013. For example:

The Philippine Star

Philippine Daily Inquirer


Conversely, some sources used PhST for the same thing, including:

Manila Bulletin

Philippine Information Agency


I did find a few instances of PHST as well (this is what tzdb used in releases 
96k through 2016j), but they were mostly in less-reliable sources. Here's an 

Philippine Daily Inquirer

So, it does appear that reliable English-language sources use alphabetic 
abbreviations for Philippine time, but (a) they don't agree, and (b) they mostly 
don't use the "PHST" abbreviation that tzdb used in 1996 through 2016.

All in all, my impression is that "PST" is more popular among reliable 
English-language sources. This is not just a measure of Google hit counts: it's 
looking at the sizes and influence of the sources. So, my inclination would be 
to go back to "PST" for Philippines time, the way tzdb had it in 1993 through 1996.

More information about the tz mailing list