IPO vs SPAC: Key Differences Explained

How does IPO vs SPAC look in practice? The table compares them on what each is, who uses it, how the price is set, what it costs, legal and tax treatment, the main risk, liquidity and a typical example.

Traditional IPO

The company hires banks and files a registration statement, the Form S-1, with the SEC. Management then pitches the shares to large investors on a road show. The banks collect orders and suggest a price, a process called book-building. They buy the shares from the company and resell them the same day. The step-by-step version is in how IPOs work.

SPAC Merger

A SPAC has already gone public. It sold units at $10, put at least 90% of the money in a trust and now has a deadline to find a target. The sponsor negotiates a merger with the private company. SPAC shareholders vote and can redeem their shares for cash from the trust. When the deal closes, the private company takes over the listing.

The SEC calls this merger a de-SPAC transaction and describes it as the functional equivalent of the target’s IPO. The de-SPAC vs SPAC guide covers each stage in detail.

In an IPO, the main cost is the bank fee, called the gross spread. It is 7% on 93.3% of US IPOs raising $30–160M. A second cost comes on the first day: if the shares jump, the company sold them too cheaply.

A SPAC spreads its cost over three layers:

• Bank feeAbout 5% to 5.5% of the SPAC’s IPO, with about 3% paid only if a merger closes.
• Founder sharesThe sponsor’s stake, usually about 20% of the SPAC after its IPO, bought for very little. It is a form of dilution for every other holder.
• WarrantsRights to buy more shares later, often at $11.50. When exercised, they add shares.

Redemptions magnify these costs. In 2022, holders redeemed an average of 85% of SPAC shares before mergers. The founder shares and fees then fall on far fewer remaining shares. The SPAC page has a worked example of how $10 of cash per share can shrink to a few dollars.

The SEC adopted new rules in 2024 to bring SPAC mergers closer to traditional IPOs. They have applied since July 1, 2024:

• Target liabilityThe target signs the merger registration statement and can be sued under Section 11, as an IPO issuer can.
• ForecastsThe legal safe harbor that protects many companies’ forecasts no longer covers SPACs.
• Reading timeMerger documents must reach SPAC shareholders at least 20 calendar days before the vote.
• Sponsor disclosureThe sponsor’s pay, its conflicts and the resulting dilution must be set out, including a table at several redemption levels.

Traditional IPO

For

Banks commit to buy the shares, so the company knows how much it raises. Many investors set the price. The process and its liability rules are long established.

Against

The 7% bank fee. Underpricing on day one. Months of preparation and a price that is set only at the end.

Verdict: the IPO remains the standard route for a company that can withstand a bank-led sale and wants a known amount of cash. SpaceX took it in June 2026. Its costs are visible and fixed at pricing.

SPAC Merger

For

The value is negotiated early with one buyer. A PIPE can add cash. The SEC notes that private-company owners may see advantages over an IPO.

Against

Founder shares, fees and warrants dilute the remaining shares. Redemptions can leave much less cash than announced. The sponsor gains from any deal.

Verdict: a SPAC merger trades the bank’s price-setting for a negotiated value and an uncertain amount of cash. Since 2021, the market for it has shrunk from 613 SPAC IPOs to 31 in 2023. The 2024 rules now give it IPO-style liability.

After an IPO, your shares usually stay in the company and become listed. A lock-up typically bars you from selling for 180 days. The wider before-and-after picture is in pre-IPO vs IPO.

After a SPAC merger, your shares are exchanged for shares of the combined company at a ratio set in the deal. A lock-up often applies. Shares not registered in the deal also fall under Rule 144. For a former shell company, that rule opens one year after it files its full business description with the SEC.

If you hold through a fund or an SPV, a special purpose vehicle that pools investors’ money for one deal, its manager decides when to sell after either route.

Common Mistakes

• Comparing headline valuesA SPAC deal value counts each SPAC share at $10. The cash behind those shares after redemptions can be much lower.
• Ignoring the sponsor’s stakeFounder shares of about 20% come out of everyone else’s ownership.
• Assuming the same exit timelineAn IPO usually means a lock-up. A SPAC merger can add a one-year Rule 144 wait.
• Reading the route as a sign of qualityNeither route says anything about the business itself. Read the filings.

IPO (initial public offering)

A company’s first sale of shares to the public, arranged by banks, after which the shares trade on an exchange.

SPAC (special purpose acquisition company)

A listed shell company that raises cash to merge with one private company.

De-SPAC transaction

The merger of a SPAC with its target, which makes the target public.

Underwriter

A bank that buys shares from the company in an IPO and resells them to investors.

Gross spread

The underwriters’ fee: the gap between what they pay the company and the offer price.

Sponsor

The firm or person that organizes a SPAC, picks its target and receives founder shares.

Founder shares

Cheap shares the sponsor receives before the SPAC’s IPO, usually about 20% of the SPAC after it.

Redemption

A SPAC shareholder’s right to hand back shares for a pro rata cut of the trust before the merger.

PIPE

A private investment in public equity: new shares sold to large investors, often alongside a SPAC merger.

Lock-up

A contract that stops existing holders from selling for a period after listing, typically 180 days after an IPO.

Figures were last checked on October 29, 2026. The rules are United States rules. SPAC market counts come from the SEC’s 2024 release, which uses SPAC Analytics data. IPO fees come from data compiled by Jay Ritter.