California Wealth Tax Odds
Will California's billionaire tax pass? Prediction markets currently put the odds at Yes with a 51.7% probability (or -107 odds), and No trading at 48.3% or +107. The measure has drawn attention from high-profile billionaires including Nvidia CEO Jensen Huang, who said he's "perfectly fine" with the proposed tax on his home state's wealthiest residents. Our California wealth tax odds tracker aggregates live pricing from Kalshi and Polymarket to show consensus probabilities on whether the measure will pass the ballot in November. Total volume stands at $567 as traders price in the measure's chances of passing. This data is updated hourly using volume-weighted average pricing (VWAP).
Probability Over Time
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Chart settings
Current Odds Snapshot
Current probabilities across platforms with liquidity indicators
YEYes
Vol $567
Spread 8.0%
Agg
51.7%↓ -3.7%California billionaire tax passes
P
56.5%
K
48.5%
NONo
Vol $567
Spread 8.0%
Agg
48.3%↑ +3.7%California billionaire tax does not pass
K
51.5%
P
43.5%
| Outcome | Aggregated | Spread | Volume | Kalshi | Polymarket |
|---|---|---|---|---|---|
YE Yes California billionaire tax passes | 51.7% ↓ -3.7% | 8.0% | $567 |
Kalshi
48.5% |
Polymarket
56.5% |
NO No California billionaire tax does not pass | 48.3% ↑ +3.7% | 8.0% | $567 |
Kalshi
51.5% |
Polymarket
43.5% |
Arbitrage Scanner
Current cross-venue opportunities with fee calculations
Pairs (Venue-to-Venue)
| Outcome | Venue Pair | Leg A (Buy) | Leg B (Sell) | Gross Spread | After Fees | Actionable | Quick Links |
|---|---|---|---|---|---|---|---|
YE Yes California billionaire tax passes |
Kalshi
→
Polymarket | Buy @ K 49¢ | Sell @ P 56¢ | +7.00% | +6.51% |
Yes | |
NO No California billionaire tax does not pass |
Polymarket
→
Kalshi | Buy @ P 44¢ | Sell @ K 51¢ | +7.00% | +6.49% |
Yes |
Outcome Diff
| Outcome A | Outcome B | Venue | A Odds | B Odds | Diff | Strategy | Quick Link |
|---|---|---|---|---|---|---|---|
YE Yes |
NO No |
Polymarket | A 56.50% | B 43.50% | +13.00% | Buy spread | |
NO No |
YE Yes |
Kalshi | A 51.50% | B 48.50% | +3.00% | Buy spread |
After-fee spreads apply the configured taker-fee model per side. Depth/slippage is not modeled in this scanner.
Methodology & Data Mapping
How we aggregate, normalize, and map cross-platform data
Default: Volume-Weighted Average Price (VWAP)
Weights each mapped market by its reported 24H USD volume at snapshot time. If volume is unavailable, we fall back to a simple average for that snapshot.
Use the VWAP/Simple toggle above the chart to switch aggregation views.
Kalshi: Official API (best bid/ask + last + 24H volume/liquidity when available).
Polymarket: Market data via their API (token prices + best bid/ask + 24H volume/liquidity when available).
Gemini: Public Prediction Markets + ticker endpoints (best bid/ask + last + 24H USD volume when available).
Event data is updated hourly. Older history is downsampled.
Each event links one or more markets per provider. We normalize labels, map provider outcomes into a shared outcome list, and merge mapped markets where appropriate.
Cross-venue spread: Max–min difference across available venue probabilities for the same outcome.
Liquidity: Relative per-venue indicators based on provider liquidity fields (no depth/slippage modeling).
Arbitrage: Computed from best bid/ask when available (otherwise mid); after-fee spread applies the configured fee model only.
Tracking California wealth tax odds
The California billionaire tax measure is now more than a policy idea: it’s a tradable event with implied probabilities reflected in prediction markets. While odds tilting below 50% reflect uncertainty and steep political hurdles, market pricing will continue to adjust as signature milestones, campaigning, polling, and legal developments unfold.
The billionaire tax market on Kalshi and Polymarket reflect crowd-sourced expectations based on a combination of political sentiment, news, fundraising momentum, and legal risk. The current odds thus reflect implied probabilities or crowd-sourced forecasts of whether or not the ballot will ultimately pass in November.
What to watch (before you trade)
- Public opinion & polls: Polling on a wealth tax, especially one targeting a tiny fraction of residents, will help shape how traders price prediction market contracts.
- Signature validation: Whether proponents can reach ballot qualification, particularly meeting signature validity thresholds, is an early structural hurdle.
- High-profile moves and billionaire exits: Asset relocation by tech founders or changes in residency patterns could feed narratives about the economic impact of the tax, shifting the public sentiment and odds accordingly.
- Legal risks: Courts may be asked to weigh in on valuation rules, residency definitions, or constitutional challenges before or after the vote, which could swiftly impact odds in either direction.
- Market prices: Keep an eye on prediction market price shifts and the news cycle, especially if you are anticipating real-world impact from the outcome. Market price shifts, especially significant ones, can act as a real-time barometer of collective expectations for passage odds. If the odds spike or drop abruptly, there is more than likely a good reason for it.
Overview and key details of the 2026 Billionaire Tax Act
California is considering one of the most talked-about tax proposals in the U.S.: a one-time 5% wealth tax on residents with a net worth above $1 billion. The idea is designed to generate tens of billions of dollars (potentially around $100 billion) to backfill state budget gaps in healthcare, education, and social services amid federal funding cuts, according to Fox Business.
Known informally as the “2026 Billionaire Tax Act,” the proposal must first qualify for the November 2026 ballot by securing nearly 875,000 valid signatures. If it reaches voters, the outcome will be decided by a simple majority at the polls that November.
The proposal
- What it is: A ballot initiative that would tax about 200–255 California billionaires a one-time 5% of net worth tax, excluding some categories like real estate and retirement accounts, with the option to pay it over five years at an extra cost.
- Revenue use: Roughly 90% of proceeds would be earmarked for healthcare services, with the rest going to education and food assistance.
Political debate
- Supporters, including powerful labor unions and some progressive politicians, argue the tax will address budget shortfalls and economic inequality.
- Opponents, from tech founders and financial leaders to Gov. Gavin Newsom, warn it could spur capital flight, discourage investment, and harm California’s economy.
- High-profile pushback includes insurers of relocation by wealthy residents and warnings from billionaires that it could incentivize departures to low-tax states.
The debate has become part of broader cultural and political conflict over inequality and state policy direction.
What’s next
1. Signature collection (early 2026)
Organizers must finalize petition efforts and gather sufficient signatures to qualify the measure for the ballot by mid-year. The deadline for turning in signatures will likely come around mid-2026.
2. Legal & strategic maneuvering
Opponents have already introduced counter-initiatives aimed at complicating or raising thresholds for tax measures, and legal challenges over valuation and enforcement could emerge.
3. Campaigning
From now until the Nov 2026 election, expect:
- Heavy advertising and public relations from both sides.
- Polling to gauge how California voters feel about a wealth tax.
- Influence of broader political trends (e.g., economic conditions, tech sector sentiment).