How many days of cash a Hawaiʻi business should hold

Hold 90 days of operating cash, with 60 as the floor. The median U.S. small business holds 27 days, and Hawaiʻi's risks run longer than that.

Hold 90 days of operating cash. Sixty is the floor. That is our standard for an island business, and it is far above what most small businesses keep. The JPMorgan Chase Institute found the median U.S. small business holds 27 cash buffer days. Shipping, storms, and the visitor calendar all last longer than that.

What the mainland research measured

The JPMorgan Chase Institute studied 597,000 small businesses and more than 470 million transactions in 2015. Its report, Cash is King: Flows, Balances, and Buffer Days, defines the measure: "Cash buffer days are the number of days of cash outflows a business could pay out of its cash balance were its inflows to stop."

The findings, quoted exactly:

• "The median small business holds 27 cash buffer days in reserve."
• "Moreover, 25 percent of small businesses hold fewer than 13 cash buffer days in reserve."
• "In contrast, 25 percent of small businesses hold over 62 cash buffer days in reserve."
• "The median small restaurant holds 16 cash buffer days in reserve."
• "The median small business in the real estate industry holds 47 cash buffer days in reserve."

That is a description of what is, not what should be. Half of small businesses could not cover a month with the doors closed. A quarter could not cover two weeks.

Why an island needs more than 27 days

Shipping. The Hawaiʻi Emergency Management Agency tells households to keep two weeks of supplies, and says why: "As the only island state in America, Hawaiʻi is in a uniquely isolated location that relies on shipping for most of its food and supplies." The kit is for the case where "a disaster like a hurricane or tsunami damages ports and supply chains." If the state plans for two weeks without a working harbor, plan for two weeks without deliveries or the customers who would have been here.

Storms. The Central Pacific Hurricane Center puts it plainly: "The hurricane season in the Pacific officially begins on June 1 and ends on November 30, however tropical cyclones can and do occur year round." Half the year carries the risk. NOAA's 2026 outlook "predicts a 70% chance of an above-normal season." Hurricane Lowell showed Kauaʻi what one storm does to a month of sales.

Seasonality. DBEDT counted 143,289 visitors to Kauaʻi in July 2025, with an average daily census of 33,639 visitors on the island. In September 2025 it counted 102,105 visitors, with an average daily census of 23,610. Divide 23,610 by 33,639 and you get 0.70. On an average September day the island holds about 30 percent fewer visitors than on an average July day. A shop staffed for July must carry itself through September on July's cash.

Put the three together: a slow season, a storm inside it, and a harbor on the state's two-week timeline. That is a 60 to 90 day problem, not a 27 day problem.

How to compute your days of cash

Days of cash equals cash you can reach today divided by your average daily cash outflow.

• Cash you can reach today: business checking, savings, and money market balances. Not the line of credit. Not invoices owed to you. Not the owner's personal account.
• Average daily outflow: add every dollar that left the business over the last 90 days. Payroll, rent, suppliers, loan payments, general excise tax, insurance, owner draws. Divide by 90.
• Divide the first number by the second.

Worked example with round numbers. A café has 40,000 in the bank. Over the last 90 days, 270,000 left the account, so daily outflow is 3,000. Forty thousand divided by 3,000 is 13 days. That café sits in the bottom quarter of the JPMorgan Chase Institute sample, one barge delay from missing payroll.

Run your own numbers in the free runway calculator. It gives days of cash and lets you email the result to yourself.

Setting your number

Our standard for Hawaiʻi:

• 90 days if your sales follow visitors or your inventory comes by barge. That describes most of Kauaʻi.
• 60 days as the floor for any island business.
• Never below 27. That is the median, and the median business is living month to month.

Nobody builds a quarter of cash in a month. Set a fixed transfer on the first of every month into an account you do not use for operations. Treat it like rent. Write the rule for touching it before you need it: the reserve is for an event that stops inflows, not for a slow month you could have planned for.

What sits next to the reserve

Cash is the first layer, and the only one that pays on the day you need it. Business interruption insurance is the second, and it pays after the adjuster finishes. SBA disaster loans are the third, and they arrive weeks after a declaration; we covered the timeline in SBA disaster loans for Hawaiʻi businesses after Hurricane Lowell. The reserve covers payroll while the other two are processed.

If you want a second opinion on where you stand, the free ten-second reading measures your business against the same standard.

Questions owners ask

Is 90 days too much for a small shop?

It is a lot. It is also how long a slow season, a storm, and a port closure take together. Start at 27, get to 60, and decide about 90 when you are there.

Does a line of credit count as cash?

No. A line can be frozen, cut, or called, and lenders tighten in the same week everyone needs them. Count only balances you can move today. Keep the line as a fourth layer behind cash, insurance, and disaster loans.

Where should the reserve sit?

In a separate business account in the business's name, with no card attached. A money market or savings account is fine. It should take one deliberate transfer to reach, not one tap.

What about my personal savings?

Keep them separate. Mixing the two hides the real number for both and flatters the business on the day you apply for a loan or file a claim. If personal money has been funding the business, the reserve is already gone.

Sources

• JPMorgan Chase Institute, Cash is King: Flows, Balances, and Buffer Days, executive summary, September 2016. Supports the definition, the 27 day median, the 13 and 62 day quartiles, and the industry figures. https://www.jpmorganchase.com/content/dam/jpmc/jpmorgan-chase-and-co/institute/pdf/jpmc-institute-small-business-report-exec-summary.pdf Fetched 2026-09-14.
• JPMorgan Chase Institute, For Small Businesses: Cash is King. Supports the sample of 597,000 businesses and 470 million transactions. https://www.jpmorganchase.com/institute/all-topics/business-growth-and-entrepreneurship/insight-cash-is-king Fetched 2026-09-14.
• Hawaiʻi Emergency Management Agency, 2-Weeks Ready in Hawaiʻi. Supports the two-week guidance and the shipping reasoning. https://dod.hawaii.gov/hiema/2-weeks-ready-in-hawai%ca%bbi/ Fetched 2026-09-14.
• NOAA, About the Central Pacific Hurricane Center. Supports the season dates. https://www.nhc.noaa.gov/aboutcphc.php Fetched 2026-09-14.
• NOAA National Weather Service Honolulu, 2026 Central Pacific Hurricane Season Outlook. Supports the 70 percent figure. https://www.weather.gov/hfo/hurricaneOutlook2026 Fetched 2026-09-14.
• DBEDT, July 2025 visitor statistics release. Supports the July Kauaʻi arrivals and daily census. https://dbedt.hawaii.gov/blog/25-34/ Fetched 2026-09-14.
• DBEDT, September 2025 visitor statistics release. Supports the September Kauaʻi arrivals and daily census. https://dbedt.hawaii.gov/blog/25-42/ Fetched 2026-09-14.

Information, not legal, tax, insurance, or financial advice.