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What Is a Post-Money SAFE?

Direct answer

A post-money SAFE is a Simple Agreement for Future Equity that calculates an investor's ownership based on the company's valuation after the investor's money has been included. This makes it much easier for founders and investors to understand exactly what percentage of the company each SAFE represents once it converts into shares.

Unlike the original pre-money SAFE, a post-money SAFE allows founders to see the cumulative ownership they have promised to all SAFE investors as they raise money. Because each SAFE is calculated using a post-money valuation, founders gain much clearer visibility into future dilution before their next priced funding round.

Today, the post-money SAFE has become the standard version published by Y Combinator and is widely used by early stage startups because it creates greater transparency for both founders and investors during fundraising.


What this page will help you understand
1What a post-money SAFE is
2How a post-money SAFE works
3Why Y Combinator introduced the post-money SAFE
4How post-money and pre-money SAFEs differ
5Why founders prefer clearer ownership calculations
6How Cairnul organizes post-money SAFE fundraising
Simple explanation

Knowing ownership from the start

Imagine dividing a pizza before everyone sits down at the table.

With a post-money SAFE, everyone agrees in advance how much of the pizza each investor will eventually receive. As each SAFE is issued, founders can immediately see how much ownership has already been promised.

That makes planning future fundraising much easier. Instead of waiting until a priced funding round to estimate ownership, founders always have a running picture of how multiple SAFEs affect the company.

The post-money SAFE was designed to remove much of the uncertainty that founders experienced with the earlier pre-money version.


The rule and the real world

What the SEC says, and what founders are actually asking

What the SEC Says
SEC EDGAR Filing

An executed post-money SAFE filed with the SEC explains that the Safe Price is determined using the Post-Money Valuation Cap together with the defined Company Capitalization. Those terms determine how many shares the SAFE converts into during a future financing event.


SEC EDGAR Filing
www.sec.gov/Archives/edgar/data/1777274/000121390020033888/ea128838ex3-1_oraclehealth.htm

A post-money SAFE does not change when the SAFE converts. It changes how ownership is calculated.

Instead of leaving founders to estimate the combined effect of several SAFEs later, each post-money SAFE establishes its ownership economics when it is signed. That gives both founders and investors greater visibility into future dilution throughout the fundraising process.


r/
What Founders Are Asking
Reddit
"Should I use a pre-money SAFE or a post-money SAFE?"
Reddit founder discussion
www.reddit.com/r/startups/comments/15iw5sj/which_is_more_founderfriendly_premoney_safe_or

The discussion usually centers on predictability rather than fairness.

Founders want flexibility while investors want certainty. The post-money SAFE was introduced to make those expectations easier to align by making ownership more transparent throughout the fundraising round.

Understanding how each SAFE affects future ownership allows founders to make informed fundraising decisions before additional investors join the round.


Cairnul conclusion

The biggest advantage of a post-money SAFE is clarity.

Instead of discovering your dilution after several SAFE investments have accumulated, you understand your fundraising position as the round develops. That makes planning future fundraising, investor conversations, and ownership much easier to manage.


How Cairnul helps

Know your ownership as you raise

A post-money SAFE is designed to make ownership easier to understand throughout a fundraising round.

Inside Cairnul, every post-money SAFE is created using the standard Y Combinator post-money SAFE. As each agreement is issued, the valuation cap, investment amount, and investor are recorded as part of the same fundraising round.

Because the ownership calculation is based on the post-money valuation, Cairnul keeps a running view of the ownership founders have already committed through outstanding SAFEs. Instead of manually updating spreadsheets after every investment, founders can see how each new SAFE fits into the overall round as it is added.

Investor records, SAFE agreements, fundraising documents, signatures, and round milestones all remain connected in one workflow. When it is time for a priced round, the information needed to understand conversion and ownership is already organized instead of scattered across multiple files.

Rather than wondering how much of the company has already been promised, founders move through fundraising with a clear view of every SAFE and its impact on future ownership.


What founders usually miss

Many founders assume that a post money SAFE is simply a newer version of a pre money SAFE with different wording.

The biggest difference is not the document itself. It is how ownership is calculated.

With a post money SAFE, each investor's ownership is determined using the company's value after their investment is included. That gives founders a much clearer picture of how much of the company has already been committed through outstanding SAFEs.

This transparency is one of the main reasons Y Combinator introduced the post money SAFE in 2018. Founders no longer have to estimate how multiple SAFEs might affect ownership once they all convert.

That does not automatically make a post money SAFE better for every situation. It simply makes future dilution easier to understand. Before issuing multiple SAFEs, founders should understand how each agreement affects future ownership and keep accurate records of every investment.


Action checklist

Know your ownership before you raise

Confirm whether you are using a post money SAFE or a pre money SAFE before raising capital.

Understand how your valuation cap affects the investor's future ownership percentage.

Keep every SAFE connected to the fundraising round in which it was issued.

Review your outstanding SAFEs before issuing new ones so you understand cumulative dilution.

Record valuation caps, investor details, and signed agreements together from the beginning.

Keep investor records, SAFE agreements, ownership information, and fundraising milestones organized in one connected workflow.

FAQ

Frequently asked questions

A post money SAFE is a fundraising agreement that calculates an investor's ownership using the company's value after the SAFE investment is included. This makes future ownership easier to predict.


A pre-money SAFE calculates ownership before the new investment is included, while a post money SAFE calculates ownership afterward. The post money version provides founders with more predictable ownership calculations.


Y Combinator introduced the post money SAFE to make dilution easier for founders and investors to understand. It allows founders to see how much ownership has already been promised through outstanding SAFEs.


No.

A SAFE is still a contract for future equity. The investor receives shares only when a qualifying event causes the SAFE to convert.


Yes.

The post money SAFE introduced by Y Combinator in 2018 has become the version most startups use for new SAFE fundraising rounds.


Keep every SAFE connected from day one

Cairnul helps founders organize investors, documents, and compliance in one place, so the whole raise stays clear from first sale to close. Join the waitlist to be among the first founders to run a cleaner, more organized round.

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Disclaimer. This content is provided for educational purposes only and does not constitute legal, tax, or investment advice. Fundraising rules, filing requirements, and fees may vary by jurisdiction and change over time. Always confirm current requirements with qualified counsel or the relevant regulator.

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What Is a Post-Money SAFE? · Cairnul