Micron's Fiscal Calendar: Why Its Quarters Don't Match Samsung's

Micron Technology does not use the calendar year. Its fiscal year ends on the Thursday closest to August 31, so its “fiscal fourth quarter 2026” ran from May 29 to September 3, 2026, and was reported on September 30. Samsung Electronics and SK hynix use calendar quarters: their third quarter ran from July 1 to September 30 and is reported in October. Micron’s quarters therefore end about one month earlier than the Korean pair’s. To compare them, line the quarters up by calendar months, not by their names.

All dates below come from the companies’ own filings and releases. Day counts are computed from the stated start and end dates, counting both ends.

How does Micron’s fiscal year work?

Micron’s annual report on Form 10-K states the rule: “Our fiscal year is the 52- or 53-week period ending on the Thursday closest to August 31.” Because the year is counted in whole weeks, its last day moves around. Fiscal 2025 ended on August 28, 2025. Fiscal 2026 ended on September 3, 2026, and the 10-K says it “contained 53 weeks”, while fiscal 2025 and 2024 each had 52.

The extra week landed in the fourth quarter. The four quarters of fiscal 2026, as given in Micron’s 10-K and its results filings, were:

Micron quarter	Period	Days	Mostly covers	Results released
Fiscal Q1 2026	Aug 29 – Nov 27, 2025	91	Sep – Nov 2025	Dec 17, 2025
Fiscal Q2 2026	Nov 28, 2025 – Feb 26, 2026	91	Dec 2025 – Feb 2026	Mar 18, 2026
Fiscal Q3 2026	Feb 27 – May 28, 2026	91	Mar – May 2026	Jun 24, 2026
Fiscal Q4 2026	May 29 – Sep 3, 2026	98	Jun – Aug 2026	Sep 30, 2026

The first three quarters are 13 weeks each; the fourth is 14 weeks. Every quarter ends on a Thursday. Micron’s September 30 release announced “results for its fourth quarter and full year of fiscal 2026, which ended September 3, 2026”, and its conference call that day was at 2:30 p.m. Mountain Time.

The quarter names are the trap. Micron’s “Q1” is mostly September to November, and its “Q4” is mostly June to August. Fiscal 2027 began on September 4, 2026; under the same rule it runs to Thursday, September 2, 2027.

How do Samsung and SK hynix report?

Both Korean companies use the calendar year. Samsung’s second-quarter release covered “the second quarter ended June 30, 2026”. SK hynix’s filings with the US Securities and Exchange Commission (SEC) define its second quarter as “the three-month period from April 1 to June 30” and its first quarter as January 1 to March 31.

Samsung reports in two steps. Shortly after a quarter ends, it publishes earnings guidance: two numbers, consolidated sales and operating profit, under Korean accounting standards (K-IFRS). For the third quarter of 2026 it did this on October 8, giving about 195 trillion won in sales and about 107.4 trillion won in operating profit. Samsung explains that Korean disclosure rules do not allow a range, so each figure is the middle of a range it also lists (194 to 196 trillion won, and 107.3 to 107.5 trillion won). It adds that the figures come before the external audit is complete. The full results, with division detail, follow later in the month. For the second quarter, guidance came on July 7 and full results on July 30, so in 2026 the guidance arrived seven and eight days after the quarter ended. Samsung’s investor relations calendar lists the third-quarter earnings call for October 29, 2026, at 10:00 a.m. Korea time.

SK hynix released its second-quarter figures on results day. On July 29 it filed a 6-K titled “Preliminary Results of Operations” for the second quarter, released at its 9:00 a.m. Seoul time call, with a note that the external audit was not yet completed. Its 6-K filings between the end of June and July 29 carried no earlier earnings estimate. On October 14 it filed notice of its third-quarter call: October 28, 2026, at 9:00 a.m. Seoul time.

For how the two Korean companies compare in high-bandwidth memory, see Samsung and SK hynix in HBM, compared.

How do the calendars line up?

Here is each company’s latest reported quarter, with its exact dates.

Company	Fiscal year	Latest reported quarter	Period	Released
Micron	52/53 weeks to the Thursday closest to Aug 31	Fiscal Q4 2026	May 29 – Sep 3, 2026	Sep 30, 2026
Samsung Electronics	Calendar year	Q2 2026 (Q3 guidance out Oct 8)	Apr 1 – Jun 30, 2026	Jul 30, 2026
SK hynix	Calendar year	Q2 2026	Apr 1 – Jun 30, 2026	Jul 29, 2026
Kioxia Holdings	April 1 to March 31	Q1 of FY2026	Apr 1 – Jun 30, 2026	Jul 31, 2026
SanDisk	52/53 weeks to the Friday nearest Jun 30	Fiscal Q4 2026	Apr 4 – Jul 3, 2026	Aug 5, 2026

And here is when the July-to-September period arrives from each:

Company	Report covering July to September	Date
Micron	Fiscal Q4 2026 (May 29 – Sep 3)	Sep 30, 2026 (released)
Samsung Electronics	Q3 2026 (Jul 1 – Sep 30)	Guidance Oct 8 (released); call Oct 29, 10:00 a.m. Korea time
SK hynix	Q3 2026 (Jul 1 – Sep 30)	Call Oct 28, 9:00 a.m. Seoul time
SanDisk	Fiscal Q1 2027 (began Jul 4)	Call Oct 29, 1:30 p.m. Pacific Time
Kioxia Holdings	Q2 of FY2026 (Jul 1 – Sep 30)	Oct 30, 18:45 Japan time

Micron’s September 30 report came eight days before Samsung’s guidance and four weeks before SK hynix’s results. But it does not cover the same months. Of the 98 days in Micron’s fiscal Q4, 33 (May 29 to June 30) fall in Samsung’s second quarter and 65 (July 1 to September 3) in its third. The Korean third quarter also includes September 4 to 30, which for Micron belongs to fiscal Q1 2027.

What about Kioxia and SanDisk?

They show two more ways to cut the year.

Kioxia Holdings (Tokyo: 285A) uses an April-to-March fiscal year: “From April 1 of every year to March 31 of the following year.” Its FY2026 therefore started in April 2026, and its first quarter of FY2026 was April to June. The quarters match the calendar ones; only the labels shift. Kioxia’s “second quarter of FY2026” is the same July-to-September period as Samsung’s “third quarter of 2026”. Kioxia’s results calendar listed the first quarter on July 31, 2026, and the second quarter is scheduled for October 30, 2026, at 18:45 Japan time. See Kioxia’s stock split and price history for the shares themselves.

SanDisk (Nasdaq: SNDK) uses weeks, like Micron, but ends its year on the Friday nearest June 30. Its 10-K says fiscal 2026 had 53 weeks and ended on July 3, 2026, and that, unlike Micron, it put the extra week in the first quarter, which had 14 weeks. Its fiscal fourth quarter ran from April 4 to July 3, 2026: 88 of its 91 days fall in April to June. So SanDisk’s quarters stay close to calendar quarters despite the different names. Its fiscal first quarter of 2027 began on July 4, and SanDisk will hold the results call on October 29 at 1:30 p.m. Pacific Time.

How do I compare one company’s quarter with another’s?

Four checks make the numbers comparable.

1. Match the months, not the names. Micron’s fiscal Q4 sits mostly in June to August. Samsung’s and SK hynix’s Q3, Kioxia’s FY2026 Q2 and SanDisk’s fiscal Q1 2027 are all close to July to September.
2. Count the weeks. Micron’s fiscal Q4 2026 had 98 days; its fiscal Q3 had 91. The extra week alone adds 7.7% more days (98 ÷ 91 = 1.077), so part of any quarter-on-quarter change in revenue comes from length. A calendar third quarter has 92 days.
3. Check the currency and accounting. Samsung and SK hynix report in won under K-IFRS. Micron and SanDisk report in US dollars and show GAAP figures next to non-GAAP ones.
4. Know which numbers are preliminary. Samsung’s early-month guidance is two rounded figures before audit. SK hynix’s results-day figures are also labeled preliminary pending audit.

For who makes which kind of memory, see Who makes what in memory. The Memory map shows all five companies’ daily share-price moves side by side, whatever fiscal quarter each one is in.