Best date for a SIP: does the SIP date matter?

Why the date matters less than people think

Each SIP instalment buys units at that day's NAV. Over 10 or 20 years, your instalments land on a mix of high and low days whichever date you pick. A fund that rises over time makes later instalments more expensive and earlier ones cheaper regardless of the day of the month. Month-to-month noise averages out. Staying invested for the full period matters far more than the day.

*[Editor: replace the paragraph above with our own date-by-date study on real NAV data when /research/sip-date-study is published, and link it here.]*

What really decides a good date

1. Cash flow. If salary arrives on the 1st, a SIP on the 1st can bounce on a bank holiday. A date between the 3rd and 10th is safer.
2. Bank cut-off and holidays. If the SIP date falls on a holiday or weekend, the instalment is processed on the next business day, and the NAV of that day applies.
3. Many platforms offer dates from 1st to 28th. Dates 29, 30 and 31 are not available everywhere because some months do not have them.
4. Equity and debt are the same. The date question applies equally to both; only the NAV changes.

Common myths

• "The 1st of the month is lowest." No pattern holds across years.
• "Wait for a dip, then start." Waiting is a decision with a cost: see SIP delay cost.
• "Split into two dates." You can, but the difference is tiny; extra SIPs mean extra mandates to track.