IPO Lock-Up Period: What Happens to Your Shares and Tax Strategy

Your company just went public. Congratulations — on paper, your equity is worth a fortune. But there's a catch: the lock-up period. For the next 90-180 days, you can't sell a single share. And if RSUs vested at IPO or you exercised ISOs, you may owe a significant tax bill with no way to sell shares to pay it.

This is the liquidity gap — and it's one of the most stressful financial situations for IPO employees. Our IPO Lock-Up Calculator models this gap and compares financing options.

What Is the IPO Lock-Up Period?

A lock-up period is a contractual restriction that prevents company insiders (employees, executives, early investors) from selling shares for a set period after the IPO — typically 180 days (about 6 months).

Why it exists: Lock-ups prevent a flood of insider selling that would tank the stock price immediately after the IPO. Underwriters require them to protect public investors and support the offering price.

Who it affects:

• All employees with vested stock or options
• Executives and board members
• Early investors and VCs
• Anyone who holds pre-IPO shares

The Liquidity Gap Problem

Here's the timeline that creates trouble:

1. IPO Day: RSUs vest, or you exercise ISOs. You owe taxes on the income.
2. Lock-up Expiration: You can finally sell shares.
3. April 15 (next year): Federal taxes are due.

If your tax due date comes AFTER lock-up expiration, you're fine — sell shares and pay. But if taxes are due BEFORE you can sell, you have a liquidity gap.

Example:

• IPO date: March 15
• 10,000 RSUs vest at $50/share = $500,000 income
• Lock-up expires: September 15 (6 months after IPO)
• Tax due: April 15 (next year) — approximately $185,000

In this scenario, lock-up expires in September but taxes aren't due until April of the following year — so there's no gap. But if the IPO were in October, lock-up would expire in April while estimated taxes are due in January and April — creating the crunch. The timing depends entirely on your IPO date.

5 Ways to Finance Your Tax Bill During Lock-Up

1. Securities-Backed Line of Credit (SBLOC)

Borrow against your locked-up shares as collateral. You get cash to pay taxes immediately.

• Typical rate: SOFR + 2-3% (currently 5.6-6.8% APR)
• Loan-to-value: Usually 50-70% of share value
• Risk: If the stock drops, you may face a margin call

Margin call mechanics: Your lender sets a maintenance LTV threshold — typically 70%. If the stock drops enough that your loan balance exceeds 70% of your collateral value, you get a margin call.

Example: You pledge $500K in shares and borrow $300K (60% LTV). If the stock drops 30% to $350K, your LTV jumps to 86% ($300K / $350K) — well above the 70% threshold. You must deposit additional collateral (cash or other securities) within 24-72 hours, or the lender liquidates your position.

During lock-up, this is especially dangerous: You cannot sell your locked-up shares to satisfy the margin call. You need other assets. To prepare:

• Keep cash reserves equal to 20-30% of your SBLOC balance as a margin call buffer
• Set a personal trigger — if the stock drops 15%, proactively repay part of the loan
• Only borrow against diversified, non-locked portfolios when possible

2. Pre-Paid Variable Forward (PVF)

An agreement with a financial institution where you receive cash now in exchange for delivering shares later.

• Typical rate: 4.5-6.2% APR (Treasury-based)
• Origination fee: 1-2% of the loan amount
• Advantage: No margin call risk (floor price is locked)
• Disadvantage: You give up some upside; minimum $500K stock value typically required

3. 401(k) Loan

Borrow up to $50,000 from your 401(k).

• Rate: Usually 8-10% (Prime + 1-2%), but you're paying interest to yourself
• Advantage: No credit check, immediate availability
• Disadvantage: Limited to $50,000; must repay within 60 days if you leave the company

4. Margin Loan (on other holdings)

If you have other investment accounts, you can borrow against those positions.

• Rate: 6-9% depending on broker and loan size
• LTV: Up to 50% of other holdings
• Advantage: Quick access, no impact on locked-up shares

5. Cash Reserves

The safest option — but requires planning years in advance.

• Start setting aside cash when the IPO seems likely
• Build reserves equal to estimated tax liability
• Zero cost, zero risk — but most employees don't plan far enough ahead

Financing Cost Comparison

Using the example above ($185,000 tax liability, 5-month liquidity gap), here's what each option costs:

Pre-IPO Tax Planning

The best way to handle the lock-up period is to plan before the IPO:

Exercise ISOs Early

Exercising ISOs while the 409A is low reduces your future tax bill. See our guide on exercising stock options before IPO.

File 83(b) Elections

If you early-exercised options, filing an 83(b) election locks in today's low FMV as your tax basis.

Spread Exercises Across Years

Don't exercise everything in the IPO year. Spreading exercises across 2-3 pre-IPO years keeps each year's tax bill manageable. For timing strategies that coordinate with a multi-year plan, see our guide on when to exercise stock options.

How Lock-Up Affects Your Capital Gains Holding Period

A critical planning detail: the lock-up period does not pause or reset your capital gains holding period clock. Time spent in lock-up counts toward the 1-year holding requirement for long-term capital gains (LTCG) treatment.

RSUs that vest at IPO: Your holding period starts on the vesting date (IPO day). After a 180-day lock-up, you've held for 6 months — you need 6 more months after lock-up expires for LTCG rates.

ISOs exercised pre-IPO: Your holding period started on the exercise date. If you exercised 8 months before IPO and the lock-up is 6 months, you've held for 14 months by lock-up expiration — already qualifying for LTCG treatment (1 year after exercise). This is a major advantage of the pre-IPO exercise strategy.

ISOs exercised at IPO: Holding period starts at exercise. After a 180-day lock-up, you've only held for 6 months — still 6 months short of LTCG qualification.

The takeaway: Exercising ISOs early (pre-IPO) means the lock-up period counts toward your LTCG holding requirement. By the time you can sell, you may already qualify for the 20% LTCG rate instead of 37% ordinary income — a difference of $85,000 on a $500K gain. See the complete 2026 federal tax brackets for current rates.

Post-Lock-Up Selling Strategy

When the lock-up finally expires, you face a new decision: how much to sell, and when?

Considerations:

• Tax bracket management: Selling everything in one year could push you into the highest bracket. Consider spreading sales across tax years.
• Lock-up expiration volume: Stock prices often dip at lock-up expiration as insiders sell. You may want to wait for the initial selling pressure to subside.
• Concentration risk: Financial advisors generally recommend holding no more than 10-15% of your net worth in a single stock.

Rule 10b5-1 Trading Plans

A 10b5-1 plan is a pre-arranged, written plan for selling shares at specific prices, quantities, or dates. You adopt the plan while you are not in possession of material non-public information (MNPI), and trades execute automatically — even during blackout periods.

Why it matters for IPO employees: As company insiders, you're restricted from trading when you have MNPI (upcoming earnings, product launches, acquisitions). A 10b5-1 plan lets you set up future trades during an "open window" and have them execute on schedule regardless of what you learn later.

2023 SEC rule changes tightened the rules:

• Officers and directors face a 90-day cooling-off period before the first trade under a new plan
• Non-officer employees face a 30-day cooling-off period
• Only one single-trade plan is allowed per 12-month period
• Plans must include a certification that you're not aware of MNPI at adoption

When to set one up: Ideally during the first open trading window after lock-up expires. Work with your company's legal/compliance team. A typical plan structure: sell a fixed number of shares per month over 6-12 months, providing systematic diversification while demonstrating no insider trading intent.

Frequently Asked Questions

How long is a typical IPO lock-up period? Most IPO lock-up periods last 180 days (about 6 months), though the range is typically 90 to 180 days. The exact duration is specified in the underwriting agreement and your individual lock-up agreement. Some high-profile IPOs have used shorter lock-ups (90 days) or structured lock-ups that release shares in stages.

Can an IPO lock-up period end early? Yes, in limited circumstances. The underwriters (typically the lead investment bank) can grant early lock-up releases at their discretion. This sometimes happens when the stock has performed well and the underwriters want to increase the public float. A secondary offering by insiders during lock-up is another mechanism. However, early release is rare — plan as if the full lock-up period will apply.

What happens to my taxes during the lock-up period? Your tax obligations are not deferred by the lock-up. If RSUs vested at IPO, that income is taxable in the year of vesting regardless of whether you can sell. If you exercised ISOs, AMT may be triggered at exercise. Estimated tax payments are still due quarterly (April 15, June 15, September 15, January 15). The lock-up simply prevents you from selling shares to cover these obligations — creating the liquidity gap.

What happens when the IPO lock-up period expires? When the lock-up expires, you gain the legal right to sell your shares on the open market. Expect increased selling volume from employees and early investors, which often causes a temporary dip in the stock price (the "lock-up expiration effect"). You may still face company-imposed trading restrictions such as blackout periods around earnings and insider trading policies. Consider setting up a 10b5-1 plan rather than selling everything on the first available day.

Can I hedge my shares during lock-up? Generally no. Most lock-up agreements prohibit not only selling but also hedging activities such as buying put options, entering short sales, or using equity swaps on company stock. Prepaid variable forwards exist in a gray area — some lock-up agreements permit them while others explicitly prohibit them. Always review your specific lock-up agreement with legal counsel before entering any hedging transaction.