When do I actually need to get a 409A valuation? What are the trigger events?

The baseline rule: you need a valuation before you grant any stock options. Not after. Before.

Beyond that, here are the real-world triggers.

You need a new 409A when:

• Before your first option grant. This is non-negotiable. No valuation, no defensible strike price.
• After a new funding round. A priced equity round is a "material event" that likely changes your FMV. Get a new valuation before granting options post-close.
• Every 12 months. Even if nothing dramatic happened, a 409A valuation expires after 12 months. You need a fresh one to keep granting options.
• After any material event. This includes things like: a significant revenue milestone (or cliff), launching a major product, a key executive departure, a down round, a bridge note with unusual terms, a secondary transaction, or receiving an acquisition offer.

The 12-month rule in practice:

Your valuation report has a date. You can use that FMV for option grants for up to 12 months, as long as no material event occurs in between. Most companies time their annual refresh to happen a month or two before their big annual grant cycle.

The mistake I see constantly: founders close a Series A in March, don't update their 409A, and then grant options in June at the old pre-round strike price. That's a problem. The funding round almost certainly changed FMV, which means those options are likely underpriced.

Rule of thumb: when in doubt, get the update. A refresh valuation is cheaper and faster than the initial one, and way cheaper than fixing mispriced grants.