One Chip Day, Four Closes: Seoul, Taipei, Tokyo and New York

The chip day starts in Asia. Tokyo and Seoul open at 09:00 local time, which is 08:00 in Singapore; Taipei opens an hour later in Singapore terms. By 14:30 Singapore time all three have closed. New York opens seven hours later and trades through the Asian night. The four regular sessions never overlap, so news hands off from one market to the next: whatever happens while a market is shut shows up in its prices at the next open. On a daily heatmap, that means each market’s “close” was set at a different hour.

When does each market open and close?

Korea, Taiwan, Japan and Singapore do not use daylight saving time, according to the IANA time zone database. The US does. Daylight saving time ends at 02:00 on Sunday, November 1, 2026 (NIST), so from Monday, November 2, New York sits one hour further from Asia. Friday, October 30 is the last US session on summer time.

Regular session	Local time	Singapore	New York, to Oct 30	New York, from Nov 2
Tokyo (TSE), morning	09:00–11:30	08:00–10:30	20:00–22:30*	19:00–21:30*
Tokyo (TSE), afternoon	12:30–15:30	11:30–14:30	23:30–02:30*	22:30–01:30*
Seoul (KRX)	09:00–15:30	08:00–14:30	20:00–02:30*	19:00–01:30*
Taipei (TWSE)	09:00–13:30	09:00–13:30	21:00–01:30*	20:00–00:30*
New York (NYSE, Nasdaq)	09:30–16:00	21:30–04:00 (22:30–05:00 from Nov 2)	09:30–16:00	09:30–16:00

* New York time on the previous evening: Asia’s Tuesday session runs on Monday night in New York.

Tokyo is the only one of the four with a lunch break, from 11:30 to 12:30 Tokyo time. Its afternoon session used to end at 15:00. The Tokyo Stock Exchange moved the close to 15:30 on November 5, 2024, when it switched to its arrowhead 4.0 trading system.

Read across the Singapore column and the day has a clear order: Tokyo and Seoul open together, Taipei follows, Taipei closes first at 13:30, and Seoul and Tokyo close at 14:30. New York opens at 21:30. When it closes at 04:00, Seoul and Tokyo are four hours from their next open. From November 2 that gap shrinks to three hours, and the gap from Asia’s close to New York’s open grows from seven hours to eight.

How is the closing price set in each market?

All four markets end the regular session with an auction rather than a last trade. Orders are collected for a few minutes and matched at one price.

• Taipei. TWSE runs a closing call auction from 13:25 to 13:30, extended to 13:33 if the close is postponed.
• Tokyo. Continuous trading stops at 15:25. Orders are taken for five minutes and the closing auction is held at 15:30, a step the exchange added with the 2024 extension.
• Seoul. KRX sets the closing price of common stocks by a single-price call auction. To prevent unfair trading, each of its call auctions ends at a random moment within 30 seconds of the scheduled time.
• New York. NYSE holds its closing auction at 16:00, after a closing imbalance period from 15:50. Nasdaq’s Closing Cross also runs at 16:00 and brings the closing orders and the order book together into a single Nasdaq closing price.

Does anything trade outside these hours?

Yes, but not in the prices a daily map uses. In Seoul, KRX added a continuous after-market from 16:00 to 20:00 on September 14, 2026, according to The Korea Times and the exchange’s own schedule. Nextrade, Korea’s alternative trading venue, runs a pre-market from 08:00 to 08:50 and an after-market from 15:40 to 20:00 Korea time. In the US, Nasdaq lists pre-market trading from 04:00 to 09:30 and after-hours trading from 16:00 to 20:00 New York time.

So Seoul’s evening trading and the US pre-market do overlap. Until October 30, 04:00 in New York is 17:00 in Seoul, which leaves three hours before Korea’s 20:00 cutoff. Prices from these sessions do not change the official close.

How does news in one market show up in the next?

Because the regular sessions do not touch, each market reacts to news that broke while it was shut. A few common patterns:

• US news reaches Asia the next morning. Anything that happens during or after the New York session, from a US chipmaker’s results to a US policy announcement, first meets Seoul, Tokyo and Taipei at their next open.
• Asian news reaches New York the same day. Announcements made during Asia’s trading day, or soon after its close, are out hours before New York opens. US-listed receipts of Asian companies, such as Taiwan Semiconductor Manufacturing Co.’s TSM on the NYSE and SK hynix’s SKHY on Nasdaq, trade on them in New York hours. See our explainers on SKHY and the Korean shares and TSM and TSMC’s Taipei shares.
• Holidays stretch the gap. Each market keeps its own calendar. Tokyo was closed on Monday, October 12, 2026 for Sports Day, while New York traded. Its next close, on October 13, was the first to follow two US sessions.

What does that look like for one week of memory stocks?

Kioxia Holdings (285A, Tokyo Stock Exchange Prime) and two Nasdaq-listed memory makers, Micron Technology (MU) and SanDisk Corp. (SNDK), illustrate the timing. The rows below are in the order the closes happened. Prices are Tokyo Stock Exchange closing prices and US regular-session closes; each move is against that stock’s previous close.

Close	Singapore time	Price	Move
Kioxia, Thu Oct 15	Oct 15, 14:30	¥12,880	−12.32%
Micron, Thu Oct 15	Oct 16, 04:00	$931.24	+1.87%
SanDisk, Thu Oct 15	Oct 16, 04:00	$1,394.83	−0.61%
Kioxia, Fri Oct 16	Oct 16, 14:30	¥13,375	+3.84%
Micron, Fri Oct 16	Oct 17, 04:00	$878.84	−5.63%
SanDisk, Fri Oct 16	Oct 17, 04:00	$1,299.30	−6.85%
Kioxia, Mon Oct 19	Oct 19, 14:30	¥13,600	+1.68%
Micron, Mon Oct 19	Oct 20, 04:00	$904.90	+2.97%
SanDisk, Mon Oct 19	Oct 20, 04:00	$1,371.12	+5.53%
Kioxia, Tue Oct 20	Oct 20, 14:30	¥13,140	−3.38%

Two things stand out. First, a shared date does not mean a shared moment. Kioxia’s October 16 close was set 13.5 hours before Micron’s, and before New York had even opened. Second, the first Tokyo session after New York’s Friday was Monday, October 19. The table shows timing only. On several days the moves point in different directions, and one market’s move does not explain the next.

What does “close” mean on the home map?

The home map puts chip stocks from Korea, Taiwan, Japan and the US on one picture. Each box uses its own market’s latest regular-session close, set in that market’s time zone. The after-hours trading described above is left out. Boxes are sized by market value in US dollars, converted at Bank of Korea (ECOS) exchange rates.

Here is what that means at 07:30 Singapore time on a Tuesday, before Asia opens:

Box	Latest close	Set at (Singapore time)	Age at 07:30
New York stocks	Monday, 16:00 New York	Tuesday 04:00	3.5 hours
Seoul and Tokyo stocks	Monday, 15:30 local	Monday 14:30	17 hours
Taipei stocks	Monday, 13:30 local	Monday 13:30	18 hours

Every box carries Monday’s date, yet the US prices already reflect a full session that Asia has not traded yet. Half an hour later Seoul and Tokyo open. While a market is open its boxes show the latest trades, refreshed about every 15 minutes (Japan and Taiwan 20 minutes delayed), and the US boxes keep Monday’s close. For most of the Asian day, then, the map mixes two dates. The status line on the map names each market’s date.

Two more details. On the map, a Taiwan close is labeled preliminary until the map has loaded the exchange’s official daily file. And moves over longer periods count each market’s own sessions: a 20-day move in Tokyo and a 20-day move in New York can start on different dates, because their holidays differ.