How Restricted Stock Units (RSUs) Work for Startups

Stop. Don't Issue RSUs Until You Read This.

As you scale, your equity philosophy has to evolve. The stock options you gave your first ten employees aren’t always the right tool for hiring your 200th. You start hearing about Restricted Stock Units (RSUs) and how all the public companies use them. They seem simpler, more predictable. They are also dangerously easy to get wrong.

For most early-stage startups (pre-seed, seed, Series A), the answer is simple: use stock options (ISOs or NSOs), not RSUs.

But if you are a later-stage founder (Series C or beyond) running a company with a significant and stable valuation, RSUs can be a powerful tool for attracting and retaining senior talent. This guide will show you how to use them without accidentally setting a tax bomb for your team.

What is a Restricted Stock Unit (RSU)?

An RSU is a promise from you to an employee: if they stay with the company for a certain period and/or other conditions are met, you will give them a specific number of shares at a future date. They don’t buy the shares; you grant them.

The conditions are called "vesting triggers." For private companies, it's critical you use two of them.

The RSU Tax Bomb: A Founder's Worst Nightmare

This is the most important part of this guide. If you only read one section, read this one.

With a simple time-based RSU (a "single-trigger" RSU), the moment the employee vests, the IRS considers the value of those shares as ordinary income. Your employee immediately owes income and payroll taxes on the full value of the vested shares, based on your current 409A valuation.

Here’s the disaster scenario: You grant an engineer RSUs that vest over 4 years. On their first anniversary, they vest $100,000 worth of your private stock. Congratulations, you just handed them a tax bill for ~$40,000 (depending on state and federal rates). But they can't sell the stock to pay the tax. It's illiquid. You haven’t given them a benefit; you’ve given them a massive financial liability.

This isn't a theoretical risk. It’s a real, company-killing mistake. You will destroy employee morale and trust.

The Only Safe Way: Double-Trigger Vesting

To prevent the tax bomb, private companies must use a "double-trigger" vesting structure. This means an employee only truly receives their shares when two separate conditions have been met:

The Service Trigger: This is standard time-based vesting. The employee must work for the company for a set period (e.g., a 4-year schedule with a 1-year cliff). · The Liquidity Trigger: A liquidity event must occur. This is usually defined as an IPO or a change of control (an acquisition).

With a double-trigger grant, an employee can be with you for five years, fully "vested" on their time-based schedule, but if the company hasn't IPO'd or been acquired, the shares have not been delivered and no tax is due. The tax event is perfectly timed with the moment they have liquid stock they can actually sell to cover the tax bill.

If your stock plan doesn’t include this for RSUs, you are doing it wrong. Full stop.

RSUs vs. Stock Options: The Strategic Choice

The choice between options and RSUs reflects your company's maturity and risk profile.

Stock Options (Typically Seed through Series B)

For the Employee: A high-risk, high-reward bet. They get the option to buy shares at a low, fixed "strike price." The goal is for the share value to grow 50-100x, making the spread massive. If the company fails, they lose nothing but a small exercise cost. · For the Founder: You’re selling the dream of explosive growth. Options are the perfect tool for aligning a small, risk-tolerant team around a speculative outcome. · Tax Point: For Incentive Stock Options (ISOs), no tax is due at grant or vesting. Tax is generally due upon exercise or sale, giving employees control.

RSUs (Typically Series C and Later)

For the Employee: A lower-risk, more predictable form of compensation. The shares are granted, not purchased. As long as the company stock has value, the RSUs have value. This is why public company employees and late-stage candidates often prefer them. · For the Founder: You’re signaling stability and confidence. You use RSUs when the company has a substantial, defensible valuation ($500M+) and a tangible path to liquidity. It becomes a tool for retention—"golden handcuffs"—because the grants have a clear dollar value. · Tax Point: With a double-trigger, tax is due when the liquidity event happens. This is less flexible for the employee but safer for everyone.

When Should You Switch from Options to RSUs?

There's no exact formula, but here’s a framework. The time is right when you can check most of these boxes:

Your 409A valuation is $500M or higher. Some say $1B. Below this, your equity is likely still too speculative for RSUs to make sense. · Your valuation is stable or consistently growing. The share price isn't swinging wildly between rounds. · You have a visible, likely path to a liquidity event within 2-3 years. You’re actively preparing for an IPO or are a clear acquisition target. · You are hiring senior talent from public companies. These candidates expect RSU-based compensation packages. Offering them makes your company competitive. · Your strike price for options is getting high anyway. When the 409A valuation makes options expensive to exercise, the appeal of a "free" RSU grant increases for candidates.

How to Structure an RSU Grant: A Worked Example

RSU grants are calculated from a target dollar value, not a raw percentage of the company. It’s about competing with market-rate compensation bands.

Let's say you want to give a new VP of Engineering a grant worth $800,000 over four years. Your latest 409A valuation pegs your share price (Fair Market Value) at $50.

Total RSUs to Grant: $800,000 / $50 per share = 16,000 RSUs · Vesting Structure: 16,000 RSUs with double-trigger vesting. The service trigger is a 4-year vest with a 1-year cliff. The liquidity trigger is an IPO or acquisition.

Scenario: The VP starts. Three years later, the company IPOs at $120 per share.

Service Vesting Met: At the 3-year mark, the VP has met the service condition for 75% of the grant: 12,000 RSUs (16,000 0.75). · Liquidity Event Occurs: The IPO is the second trigger. A few days after the IPO (after a brief "lock-up" period), the 12,000 RSUs are settled and the shares are delivered. · Calculating Taxable Income: The income is the value of the shares at settlement. 12,000 shares $120/share = $1,440,000 in taxable income. · The "Sell-to-Cover" Withholding: The VP doesn’t get all 12,000 shares in their account. The company is required to withhold taxes. It does this by automatically selling a portion of the shares on the employee's behalf. Assuming a 40% total tax rate (federal + state): - Tax owed: $1,440,000 40% = $576,000 - Shares to sell for tax: $576,000 / $120 per share = 4,800 shares. · Net Shares Delivered: The VP receives the remaining shares: 12,000 - 4,800 = 7,200 shares .

The final 4,000 RSUs will vest and settle on their 4-year anniversary, with taxes calculated and withheld based on the stock price at that time.

Common Founder Mistakes with RSUs

Using Single-Trigger Vesting. We’ve covered this, but it’s worth repeating. This is the cardinal sin. It’s malpractice that puts your team at financial risk. · Using RSUs When You're Too Early. Granting RSUs at a $50M valuation signals that you don't understand how equity works. Stick to options until you have the scale and stability to back up RSU grants. It protects your team and your credibility with investors. · Poor Communication. Candidates see a big dollar number and don’t understand the triggers or the tax withholding. You MUST explain it clearly. Create a one-page document with a worked example like the one above and give it to every candidate to whom you offer RSUs. · Not Understanding Employee Questions (like 83(b) Elections). Employees familiar with stock grants might ask if they can file an 83(b) election to pay taxes early at a lower valuation. For double-trigger RSUs, the answer is no. Because the shares aren't delivered until both triggers are met (which could be years after grant), there is no property "transferred" at grant to be taxed on. Knowing this helps you answer questions correctly and builds trust.

How to Apply This Next Week

Diagnose Your Company Stage. Use the checklist above. Are you valued at over $500M with a clear path to liquidity? Be honest. If not, table this conversation for a year. · Engage Experienced Legal Counsel. This is not a time to use a cheap online service or an inexperienced lawyer. You need a firm that has structured hundreds of late-stage equity plans. Ask them specifically how they structure their double-trigger RSU language. · Build Your Compensation Model. Before you grant anything, build out your compensation bands using market data (Levels.fyi, Pave, Option Impact are places to start). Determine the target total compensation ($ cash + $ equity) for every role and level. The RSU grant size will be derived from this model. · Model the Dilution. Create an RSU pool in your cap table (similar to an option pool). Understand how it will dilute founders, investors, and existing employees. A typical RSU pool might be 1-5% of the company, refreshed annually. · Draft Your Employee One-Pager. Start writing the document that explains your RSU plan in simple terms. If you can't explain how vesting, triggers, and sell-to-cover taxes work in a simple way, you don’t understand it well enough yourself.