---
title: "California billionaire tax may yield less revenue, study says"
publication: "MediaBias News"
url: "https://mediabias.news/business/california-billionaire-tax-may-yield-less-revenue-study-says"
api: "https://mediabias.news/api/v1/stories/california-billionaire-tax-may-yield-less-revenue-study-says"
markdown: "https://mediabias.news/business/california-billionaire-tax-may-yield-less-revenue-study-says.md"
audio: "https://mediabias.news/api/audio/california-billionaire-tax-may-yield-less-revenue-study-says"
category: "Business & Economy"
area: "United States"
published: "2026-10-22T00:25:17.690Z"
source_reported: "2026-10-19T18:16:37.000Z"
updated: "2026-10-22T00:25:17.690Z"
trust_score: 68
critic_score: 95
hype_score: 15
assessment_type: "coverage-and-source-reporting-analysis"
fact_check_status: "not-performed"
coverage_measured: "2026-10-22T02:15:29.551475+00:00"
---

# California billionaire tax may yield less revenue, study says

*Stanford economists caution a proposed wealth tax could lead to significant income tax losses.*

**Scores for the source reporting** (0-100, assessing the original journalism this article was written from, not this write-up): 

- Trust 68 of 100, higher is better. Trust 68: multiple named sources and cited NBER working paper provide evidence, but only one outlet covered the story.
- Craft 95 of 100, higher is better. Critic 95: explains relevance, includes quotes from union and economists, separates facts, gives specific figures and next steps.
- Hype 15 of 100, lower is better. Hype 15: language is measured; no sensationalism or clickbait beyond factual reporting.

Scored by MediaBias News; method at https://mediabias.news/methodology.

**The short version**

- Stanford economists Benjamin Jaros and Joshua Rauh estimate California's proposed billionaire tax would generate about $30 billion, significantly less than the $100 billion projected by proponents.
- Seven billionaires, including Peter Thiel, Larry Page, and Sergey Brin, have relocated from California, removing an estimated $540 billion or 30% of the state's billionaire wealth.
- The economists predict California could lose $1 billion to $3.5 billion annually in income tax revenue due to this decrease in its billionaire population.
- A Citrin-Politico poll indicates voter sentiment is divided, with 46% favoring the proposition and 43% opposing it.

Stanford economists Benjamin Jaros and Joshua Rauh have estimated that California's proposed billionaire tax, Proposition 40, may generate approximately $30 billion in revenue. This figure is considerably lower than the $100 billion projected by supporters of the measure. The economists' working paper, published by the National Bureau of Economic Research, suggests that the tax, which would impose a one-time 5% state tax on billionaire wealth, could be offset by future income tax losses.

The study highlights that seven billionaires, including Peter Thiel, Larry Page, and Sergey Brin, have moved out of California. This exodus represents an estimated $540 billion, or 30%, of the state's total billionaire wealth, removing it from potential taxation. Jaros and Rauh calculated that California could lose between $1 billion and $3.5 billion annually in income tax revenue as a result of its shrinking billionaire population. They concluded that these persistent losses, when valued in today's dollars, could exceed the wealth tax proceeds by about $39 billion.

## Disagreement on tax purpose and impact

The Service Employees International Union-United Healthcare Workers West (SEIU-UHW), which introduced the ballot measure, disputed the Stanford study's findings. Union vice president Debru Carthan stated that the tax's sole purpose is to ensure billionaires pay their fair share to prevent a healthcare system collapse and allow millions of Californians to keep their healthcare without premium increases. In contrast, the Stanford economists Jaros and Rauh wrote that their findings suggest the Billionaire Tax Act will not fulfill its intended functions, as behavioral responses prior to voting have already eroded much of the projected tax base. Other economists, including Nobel laureates Daron Acemoglu and Joseph Stiglitz, have supported the measure, noting California's increased venture funding since the tax was announced and arguing for public spending on essential services funded by the ultra-wealthy.

## What the coverage left out

No left- or right-rated reports were available for this story. The centre-rated report did not include the views of economists who support the measure, such as Daron Acemoglu and Joseph Stiglitz, beyond a brief mention that they have signed their support.

## Who covered it

Shares of the 32 covering outlets with a published leaning rating:

- Left: 9% (3)
- Centre: 41% (13)
- Right: 50% (16)

5 of 37 covering outlets carried no usable leaning rating and were excluded from those percentages. Coverage measured 2026-10-22T02:15:29.551475+00:00.

**Coverage watch:** developing. Checked 9 times; 0 checks found a material change. Most recently checked 2026-10-22T02:30:26.248Z.

## How the sides framed it

### Left

No separate framing summary.

### Centre

- The centre-rated report from CBS News led with the caution from Stanford economists that California's proposed billionaire tax could result in less state revenue. It detailed the economists' estimate of $30 billion in potential revenue, contrasting it with the $100 billion projected by proponents. The report highlighted the departure of seven billionaires from California, representing $540 billion in wealth, and the projected annual income tax losses of $1 billion to $3.5 billion. It also included the union's refutation of the study and a poll showing divided voter sentiment, with 46% in favour and 43% opposed to Proposition 40.

### Right

No separate framing summary.

**Provisional coverage gap:** left. The watch is not closed, so this is not yet a settled blindspot finding.

## Factuality profile of the covering outlets

These are published factuality ratings of the outlets, not a verdict on whether this story or its claims are true.

- low: 1
- mixed: 2
- high: 19
- unknown: 5
- veryHigh: 10

## Verification scope

This page compares coverage and scores the source reporting. It is not a ClaimReview verdict on whether the underlying event or claim is true.

## Original reporting this was written from

- [DiarioBitcoin](https://diariobitcoin.com/estados-unidos/impuesto-a-multimillonarios-en-california-economistas-advierten-una-perdida-neta-de-usd-39-000-millones) — California Billionaires Tax: Economists Warn a Net Loss of USD 39 Billion
- [Fortune](https://fortune.com/2026/10/21/california-billionaire-tax-prop-40-stanford-study-39-billion-loss) — Billionaires fleeing California could turn a $30 billion tax windfall into a $39 billion loss, Stanford economists warn
- [MSNBCTV NEWS](https://msnbctv.news/californias-billionaire-tax-could-leave-the-state-39-billion-poorer-stanford-economists-warn) — California’s billionaire tax could leave the state $39 billion poorer, Stanford economists warn
- [The San Joaquin Valley Sun](https://sjvsun.com/california/economists-billionaire-tax-would-hurt-not-help-california) — Economists: billionaire tax would hurt, not help, California
- [thedailybs.com](https://thedailybs.com/2026/10/20/economists-billionaire-tax-would-hurt-not-help-california) — Economists: Billionaire tax would hurt, not help, California - The Daily Bo Snerdley
- [Chronicle-Tribune](https://chronicle-tribune.com/news/wire/economists-billionaire-tax-would-hurt-not-help-california/article_213efd96-7515-5a30-ba77-ed6537208a37.html) — Economists: Billionaire tax would hurt, not help, California
- [Columbia Gorge News](https://columbiagorgenews.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_ff94de62-f14f-5822-8d84-764b63677d40.html) — Economists: Billionaire tax would hurt, not help, California
- [Daily Post-Athenian](https://dailypostathenian.com/news/national/article_886b7d26-7fb6-5277-a681-ebdcbb03e19b.html) — Economists: Billionaire tax would hurt, not help, California
- [Fairfield Sun Times](https://fairfieldsuntimes.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_7c4f7dfa-df75-544f-97a0-47645ca4185b.html) — Economists: Billionaire tax would hurt, not help, California
- [Fort Wayne Business Weekly](https://fwbusiness.com/news/national/article_60b23b98-c77b-5fb4-bbf0-ca72d8e19244.html) — Economists: Billionaire tax would hurt, not help, California
- [KAKE News](https://kake.com/economists-billionaire-tax-would-hurt-not-help-california/article_b3ed8181-cf41-525e-8284-bb62b8cefef9.html) — Economists: Billionaire tax would hurt, not help, California
- [KPVI](https://kpvi.com/interests/economists-billionaire-tax-would-hurt-not-help-california/article_314b0f41-26a7-5291-8956-642eb2bbf1c5.html) — Economists: Billionaire tax would hurt, not help, California
- [KTEN](https://kten.com/news/economists-billionaire-tax-would-hurt-not-help-california/article_6d8bcab3-8163-5162-b8b6-ccb2a33cd1b5.html) — Economists: Billionaire tax would hurt, not help, California
- [Mountain Democrat](https://mtdemocrat.com/news/state/economists-billionaire-tax-would-hurt-not-help-california/article_48e7b154-c33b-5ea1-abcd-0aad84d1fa04.html) — Economists: Billionaire tax would hurt, not help, California
- [News-Graphic.com](https://news-graphic.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_c9e76cd9-631a-5a8e-9400-8a7eee25a492.html) — Economists: Billionaire tax would hurt, not help, California
- [News-Herald](https://news-herald.net/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_cb711599-5659-578c-8856-9fc0c1ad243c.html) — Economists: Billionaire tax would hurt, not help, California
- [News-Topic](https://newstopicnews.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_6cd72cce-1358-5588-975b-b11d0ef287e1.html) — Economists: Billionaire tax would hurt, not help, California
- [Purdue Exponent](https://purdueexponent.org/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_3b0a91fa-59ee-5e40-b129-a3a576f6a4e9.html) — Economists: Billionaire tax would hurt, not help, California
- [Star Local](https://starlocalmedia.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_e257c6e8-eb66-5c7b-878c-3c29a6814631.html) — Economists: Billionaire tax would hurt, not help, California
- [The Center Square](https://thecentersquare.com/california/article_4e3f6dd8-3768-4975-b5a4-baf12c0e5609.html) — Economists: Billionaire tax would hurt, not help, California
- [The Daily Herald](https://rrdailyherald.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_ee0084af-98ba-57e8-8860-dca2c29e43af.html) — Economists: Billionaire tax would hurt, not help, California
- [The Elkhart Truth](https://elkharttruth.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_24080c18-2d0f-5ec1-9da3-bf92cf1c040a.html) — Economists: Billionaire tax would hurt, not help, California
- [The Guam Daily Post](https://postguam.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_1bb81eb5-d516-5dd1-970f-ec5d0cb8d246.html) — Economists: Billionaire tax would hurt, not help, California
- [The Herald Palladium](https://heraldpalladium.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_8af705a8-0a8d-5d41-8d0c-64ccd9257aaa.html) — Economists: Billionaire tax would hurt, not help, California
- [The Mountain Press](https://themountainpress.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_d0b63e13-1c37-561e-a410-0b26b5b300e3.html) — Economists: Billionaire tax would hurt, not help, California
- [The Penn](https://thepenn.org/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_d069f480-d33c-5cdb-a1a0-84e584600d76.html) — Economists: Billionaire tax would hurt, not help, California
- [WVII / Fox Bangor](https://foxbangor.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_31e3b28b-c2d9-55c1-9f8b-51930f7927b4.html) — Economists: Billionaire tax would hurt, not help, California
- [Webster County Citizen](https://webstercountycitizen.com/news/national/article_4a711009-a36e-5fab-8c98-4e2174265d33.html) — Economists: Billionaire tax would hurt, not help, California
- [Your Alaska Link](https://youralaskalink.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_5b24ac8d-3971-5871-a8d1-d067402a5e3d.html) — Economists: Billionaire tax would hurt, not help, California
- [romesentinel.com](https://romesentinel.com/ce/news/economists-billionaire-tax-would-hurt-not-help-california/article_99ecaadf-9e83-5aae-bbba-f7feafe27bd5.html) — Economists: Billionaire tax would hurt, not help, California
- [Just the News](https://justthenews.com/nation/states/center-square/economists-billionaire-tax-would-hurt-not-help-california) — Billionaire tax would hurt California, not help, according to some economists
- [Owensboro Messenger-Inquirer](https://messenger-inquirer.com/news/national/economists-billionaire-tax-would-hurt-not-help-california/article_705c6884-b300-59d7-b23b-23bc3032cc3a.html) — Economists: Billionaire tax would hurt, not help, California
- [Townhall](https://townhall.com/news/dmitri-bolt/2026/10/20/ca-billionaire-tax-projected-to-lose-30-billion-n2684983) — Stanford Researchers Just Gave California’s Billionaire Tax a Cold Dose of Reality
- [RealClearMarkets](https://realclearmarkets.com/2026/10/20/worst-case_california_wealth_tax_scenario_it_succeeds_1212544.html) — Worst-Case California Wealth Tax Scenario? It 'Succeeds'
- [Marginal REVOLUTION](https://marginalrevolution.com/marginalrevolution/2026/10/the-california-billionaire-tax.html) — The California billionaire tax is very likely a net revenue loser
- [CBS News](https://cbsnews.com/news/california-billionaire-tax-stanford-study) — California billionaire tax could leave state with less revenue, Stanford study cautions
- [BizToc](https://biztoc.com/x/f8b6d0c3a1947217) — California billionaire tax could backfire, Stanford study says

## Questions

**How much revenue could California's proposed billionaire tax generate?**

Stanford economists Benjamin Jaros and Joshua Rauh estimate the tax could generate about $30 billion. This is significantly less than the $100 billion projected by proponents of the measure, Proposition 40.

**Why might the tax generate less revenue than expected?**

The Stanford study suggests that billionaires may move out of California in response to the tax, thereby removing wealth from potential taxation. This wealth migration could lead to substantial losses in state income tax revenue, potentially offsetting the revenue gained from the wealth tax itself.

**What is the projected impact on California's income tax revenue?**

Economists predict that California could lose between $1 billion and $3.5 billion annually in income tax revenue due to a shrinking billionaire population. If these losses are permanent, their value could exceed the wealth tax proceeds by approximately $39 billion.

**How do voters feel about the proposed billionaire tax?**

A Citrin-Politico poll indicates that voter sentiment is divided. According to the poll, 46% of likely voters favor Proposition 40, while 43% oppose it, suggesting a close contest ahead of the vote.

---

MediaBias News — https://mediabias.news. Reproduced from https://mediabias.news/business/california-billionaire-tax-may-yield-less-revenue-study-says. Please cite as: MediaBias News, "California billionaire tax may yield less revenue, study says", https://mediabias.news/business/california-billionaire-tax-may-yield-less-revenue-study-says