The Prediction Markets

Bank of Japan Decision in December?

Full timeKickoff Waiting for the venues to settle
Traded
$22K
Venues
Polymarket, Kalshi
Prices updated
just now
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What the markets expect

25 bps increase 72.7%

Next is No change at 25.1%. The venues differ most on No change (Polymarket 24.5%, Kalshi 28%), a 3.5-point gap.

50+ bps decrease 0.6%25 bps decrease 0.8%No change 25.1%25 bps increase 72.7%50+ bps increase 0.8%

Ordered from largest cut to largest hike.

Odds by venue

Fair chance strips out each venue’s built-in margin (its prices add up to more than 100%), then blends the venues by how much has traded there, so the outcomes add up to 100%. Best Yes price is the cheapest ask across venues, and the payout is what a winning $100 stake returns before fees. Open a row for each venue’s contract name, bid and ask, and how closely their rules match.

Prices come from our regular polls of each venue, the oldest 2 min ago. Ages are as of when this page was built.

  • Polymarket
  • Kalshi
50+ bps decreaseArb
0.6%
Polymarket 0.5%polled, 31s agoKalshi 1%polled, 2 min agoBest Yes 0.9¢ on Polymarket, $100 pays $11,111 (111x)
Polymarket
Contract
50+ bps decrease
Last price
0.5%
As of
Polled just now
Buy Yes
0.9¢
Sell Yes
0.1¢
$100 on Yes pays
$11,111 (111x)
Volume
$2K
Trade this on Polymarket
Kalshi
Contract
Cut more than 25bps
Last price
1%
As of
Polled 2 min ago
Buy Yes
2¢
Sell Yes
1¢
$100 on Yes pays
$5,000 (50.0x)
Volume
$94
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

Buying on Polymarket at 0.9¢ and selling on Kalshi at 1¢ nets 10 bps before fees.

25 bps decrease
0.8%
Polymarket 0.7%polled, 31s agoKalshi 1%polled, 2 min agoBest Yes 1¢ on Polymarket, $100 pays $10,000 (100x)
Polymarket
Contract
25 bps decrease
Last price
0.7%
As of
Polled just now
Buy Yes
1¢
Sell Yes
0.4¢
$100 on Yes pays
$10,000 (100x)
Volume
$1K
Trade this on Polymarket
Kalshi
Contract
Cut 25bps
Last price
1%
As of
Polled 2 min ago
Buy Yes
2¢
Sell Yes
1¢
$100 on Yes pays
$5,000 (50.0x)
Volume
$94
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

No arbitrage: the best bid elsewhere is 1¢, at or below the cheapest ask of 1¢.

No changeArb
25.1%
Polymarket 24.5%polled, 31s agoKalshi 28%(27.2% fair)polled, 2 min agoBest Yes 26¢ on Polymarket, $100 pays $385 (3.85x)
Polymarket
Contract
No change
Last price
24.5%
As of
Polled just now
Buy Yes
26¢
Sell Yes
23¢
$100 on Yes pays
$385 (3.85x)
Volume
$5K
Trade this on Polymarket
Kalshi
Contract
Maintain current rate
Last price
28%
Fair, margin removed
27.2%
As of
Polled 2 min ago
Buy Yes
29¢
Sell Yes
28¢
$100 on Yes pays
$345 (3.45x)
Volume
$608
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

Buying on Polymarket at 26¢ and selling on Kalshi at 28¢ nets 200 bps before fees.

25 bps increaseArb
72.7%
Polymarket 74%polled, 31s agoKalshi 72%(69.9% fair)polled, 2 min agoBest Yes 72¢ on Kalshi, $100 pays $139 (1.39x)
Polymarket
Contract
25 bps increase
Last price
74%
As of
Polled just now
Buy Yes
75¢
Sell Yes
73¢
$100 on Yes pays
$133 (1.33x)
Volume
$8K
Trade this on Polymarket
Kalshi
Contract
Hike 25bps
Last price
72%
Fair, margin removed
69.9%
As of
Polled 2 min ago
Buy Yes
72¢
Sell Yes
71¢
$100 on Yes pays
$139 (1.39x)
Volume
$3K
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

Buying on Kalshi at 72¢ and selling on Polymarket at 73¢ nets 100 bps before fees.

50+ bps increase
0.8%
Polymarket 0.7%polled, 31s agoKalshi 1%polled, 2 min agoBest Yes 1.1¢ on Polymarket, $100 pays $9,091 (90.9x)
Polymarket
Contract
50+ bps increase
Last price
0.7%
As of
Polled just now
Buy Yes
1.1¢
Sell Yes
0.3¢
$100 on Yes pays
$9,091 (90.9x)
Volume
$2K
Trade this on Polymarket
Kalshi
Contract
Hike more than 25bps
Last price
1%
As of
Polled 2 min ago
Buy Yes
2¢
Sell Yes
1¢
$100 on Yes pays
$5,000 (50.0x)
Volume
$188
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

No arbitrage: the best bid elsewhere is 1¢, at or below the cheapest ask of 1.1¢.

Possible arbitrage before fees: buy No change on Polymarket at 26¢, sell on Kalshi at 28¢ (200 bps). Check the rules below before trading. See all live spreads

Mostly the same bet: 4 differences

Where they differ

  • Buckets assume 25 bp steps: Kalshi 'Cut >25bps' / 'Hike >25bps' and Polymarket '50+ bps' differ for a move strictly between 25 and 50 bps; Kalshi 'Cut 1-25bps' also covers moves under 25 bps.
  • Polymarket names the reference rate per bank (Fed: upper bound of the target range; ECB: deposit facility rate; BoJ: uncollateralized overnight call rate); Kalshi settles on the announced action.
  • Both settle on the scheduled meeting in the named month; an unscheduled move between meetings counts for neither.
  • Trading closes at different times: Dec 18, 2026, 12:00 AM UTC on Polymarket and Dec 18, 2026, 3:29 AM UTC on Kalshi.
Polymarket
Polymarket resolves via:
UMA optimistic oracle, source: boj.or.jp
Kalshi
Kalshi resolves via:
Kalshi (CFTC-regulated exchange), source: Trading Economics
Show full rule comparison
  • Buckets assume 25 bp steps: Kalshi 'Cut >25bps' / 'Hike >25bps' and Polymarket '50+ bps' differ for a move strictly between 25 and 50 bps; Kalshi 'Cut 1-25bps' also covers moves under 25 bps.
  • Polymarket names the reference rate per bank (Fed: upper bound of the target range; ECB: deposit facility rate; BoJ: uncollateralized overnight call rate); Kalshi settles on the announced action.
  • Both settle on the scheduled meeting in the named month; an unscheduled move between meetings counts for neither.
  • Trading closes Dec 18, 2026, 12:00 AM UTC on Polymarket and Dec 18, 2026, 3:29 AM UTC on Kalshi.

Summarized from each venue’s published rules; the venue’s own rules page is the final word.

How the odds have moved

The top 3 outcomes on both venues, with the consensus between them. Hover for exact values.

  • 25 bps increase
  • No change
  • 25 bps decrease

Live prices for 25 bps increase

What it costs to buy Yes, what you would get selling it, and the last trade on each exchange, updating as orders change. Hover a status for timing details.

Order books

Each venue’s resting orders for the selected outcome’s Yes contract, side by side. Top of book streams live; depth refreshes every 15 seconds.

Combined depth · both venues

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Polymarket

Open on Polymarket ↗

Top of book

Connecting
Best bid
—
Spread
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Best ask
—

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Depth · top 8 levels

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Recent trades

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Kalshi

Open on Kalshi ↗

Top of book

Connecting
Best bid
—
Spread
—
Best ask
—

Waiting for the first live quote…

Depth · top 8 levels

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Recent trades

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What your stake buys

Enter a stake to see where it buys the most after fees, using each venue’s live order book.

$
Buy

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Buys at the asks resting now (taker orders), cheapest after fees first, from order-book snapshots up to 15 seconds old. Fees: Kalshi 0.07 × price × (1 − price) per share, rounded up to the cent; Polymarket 0.05 × price × (1 − price) per share (other / general rate). Fee calculator. Estimates only, not advice.

About this market

Live prediction market odds for "Bank of Japan Decision in December?". 25 bps increase leads at 72.7%. Next is No change at 25.1%. $22K has traded across 5 outcomes on Polymarket and Kalshi. The market is expected to resolve by Dec 18, 2026.

This market will resolve according to the change in basis points in the uncollateralized overnight call rate resulting from the December 2026 meeting of the Bank of Japan’s Policy Board, relative to the level it was prior to this meeting. The resolution source will be official information from the Bank of Japan, including the statement or release from its December 2026 Monetary Policy Meeting, scheduled for December 17-18, 2026, as listed on the official Bank of Japan calendar (https://www.boj.or.jp/en/mopo/mpmsche_minu/index.htm). This market may resolve as soon as the statement or release of the Bank of Japan’s Policy Board resulting from its December 2026 meeting with relevant data is issued. If the specified rate is defined by an upper and lower bound, the relevant change will be the change to the upper bound. If the specified rate is changed to a level not expressed in the displayed options, the change will be rounded according to the following guidelines. Increases or decreases of less than 25 bps will be rounded to 25 bps (e.g. an increase or decrease of 10 bps would be considered to be an increase or decrease of 25 bps). Increases or decreases of greater than 25 bps will be rounded to the nearest 25 bps and will be rounded away from 0 in cases of equidistance (e.g., an increase or decrease of 37.5 bps would be considered to be an increase or decrease of 50 bps). Displayed options of “Increase” or “Decrease” will include policy rate increases or decreases of any size. If the specified meeting is postponed to a date and time before the start of the next scheduled meeting, this market will resolve based on the outcome of that postponed meeting. If the specified meeting is cancelled, or postponed such that no decision is announced by the start of the next scheduled meeting, this market will resolve to the “No Change” bracket. Emergency changes to the specified rate not resulting from the specified meeting will not be considered.

Questions

What does the consensus price mean?

It is the price of a Yes contract that pays $1 if the outcome happens. A 14¢ price means traders put the chance near 14%. Where two venues list the same outcome, we blend their last prices, weighting the venue with more trading volume more heavily (neither counts for less than a quarter). When only one outcome can win, each venue’s prices add up to a little over 100% (its margin); the fair chance removes that margin so the outcomes add up to exactly 100%.

How is the payout worked out?

A Yes contract pays $1 if it wins, so at the best ask a $100 stake buys 100 ÷ ask contracts. At 18¢ that is about 555 contracts, paying $556 (5.56x) if Yes happens. Venue fees and price slippage on larger orders are not included.

Why do the venues show different prices?

Each venue has its own traders, fees and order book. Contracts can also settle on slightly different terms, which is why each row lists how closely the rules match.

Is a price gap an arbitrage?

Only when you can buy Yes on one venue below what someone pays for Yes on the other, after fees, and both contracts settle the same way. We show the executable bid and ask so you can check.

How fresh are these prices?

Venue prices refresh every few minutes, and the order book and live quotes stream continuously. Each venue’s card shows when we last observed it.

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