I feel that there's not much info about HSP experience on the internet, so I decided to post my experience here, so that others can reference, feel free to add in more points.
SAF Personnel Admin Centre will notify you 3 months before your birthday, to book for a HSP appointment.
However, if your unit screwup and didn't send you the notification, you need to call them, to ask them to book for you.
Their phone number can be found in this link.
https://www.mindef.gov.sg/web/porta...e/medical-appointments/personnel-admin-centre
You won't be able to go for IPPT/NS FIT until you cleared your HSP.
Once you book, you will receive the SAF100 2 weeks before the appointment, it will be a 1/2 day callup.
The SAF100 will tell you what attire to wear to go in, normally is collar shirt with long pants.
You will need to show the SAF100 at the guardhouse in order to change pass to go in.
The test done will be e.g. blood test, ECG, eye sight test, height and weight, urine, etc.
After that, the MO will ask you a few questions, then tell you to check NS portal for the blood test results.
I got the blood test results after around 2 days in NS portal eHealth.
The entire HSP will take around 2 hours, but it depends on how crowded the Medical Centre is.
The HSP outcome status will be pending in NS portal eHealth for a while.
It will take around 2 to 3 months for it to finalize.
You will receive SMS to inform you to check NS Portal eHealth to see the HSP outcome.
After that, it will show either Low, Moderate, High.
Only Low, then you can take IPPT.