A weekend at Okoboji is cheapest and easiest to get in the last five weeks of the season. From August 16 our rates drop by half, and after September 7 the weekend premium comes off entirely, so two nights are priced at 40% of the weekly rate instead of 55%. Put those together and a mid-September Friday and Saturday runs at roughly a third of what the same two nights cost in July. The water is still warm. The first ten days of September average 73°F, which is warmer than the middle of June. What you give up is the staffed programme: skiing, sailing and the specialty cruises are not normally running after August 16, and the amusement park winds down after Labor Day. For a certain sort of guest that is the entire appeal.
Key Takeaways
- Rates fall 25% from August 9 and 50% from August 16, through closing on September 19.
- The weekend premium applies only between June 1 and September 7. Outside that, weekends are priced like any other night.
- Early September water is warmer than mid-June water.
- The staffed activity programme is not normally running after August 16. We would rather you knew that now.
- Labor Day is the exception. It carries its own holiday rate and is not discounted.
How a short stay is priced
Everything here is quoted as a weekly rate, and shorter stays are prorated off it. The first three nights cost 20% of the week each. Nights four through seven cost 10% each. So the longer you stay, the cheaper each night gets.
| Nights | Share of the weekly rate |
|---|---|
| 1 | 20% |
| 2 | 40% |
| 3 | 60% |
| 4 | 70% |
| 5 | 80% |
| 6 | 90% |
| 7 | 100% |
Between June 1 and September 7 there is a weekend premium on top of that. A Friday or Saturday on its own is 35% of the weekly rate, and a two-night weekend is 55% rather than 40%. That premium exists because in high summer a weekend booking has to fit between two weekly ones, and often there is nothing to fit it into. Ask us in mid-July and the honest answer is frequently that we have nothing.
Add 12% tax to whatever the number is, 5% Iowa sales and 7% hotel. And we do not take credit or debit cards, which surprises people every year, so plan for that before you arrive rather than at the desk.
Why late-season weekends are cheaper twice over
Two separate things happen in the back half of August, and they compound.
The first is the seasonal discount. From August 16 to closing, rates are half. The second is that the weekend premium stops on September 7, so a Friday and Saturday goes back to being 40% of the week rather than 55%.
Work it through. Two nights in July cost 55% of the full weekly rate. The same two nights on September 12 cost 40% of a weekly rate that has already been halved, which is 20% of the peak figure. Same unit, same dock, same lake, about a third of the money.
And there is room. The whole reason a July weekend is expensive is that it is squeezed between weekly bookings. In September it is not squeezed at all.
The 2026 dates, and 2027 if you are planning ahead
For the 2026 season, which closes September 19:
- In-season weekly rates: June 29 to August 9
- 25% off: June 7 to June 29, and August 9 to August 16
- 50% off: before June 7, and from August 16 to closing
For 2027, the season again runs May 1 to September 19. The 25% window is June 13 to 29 and August 15 to 22, and the 50% window is before June 13 and from August 22. Worth writing down now if you are the sort who books a year out, and a good many of our guests are.
One exception to all of it. Labor Day weekend has its own holiday rate and sits outside the discount. If Labor Day is the weekend you want, call and get a number rather than doing the arithmetic above and being disappointed.
What you give up
This is the part most resorts leave off the page, so here it is plainly. In the 50% period, from August 16, the published policy is that the following are not normally offered:
- Water skiing and ski instruction
- Sailing on the 28-foot scow, which runs weather and staffing permitting even in high season
- The History Cruise and the Million Dollar Home Cruise
- The daily recreation programme
- Full room service, which becomes daily towel service from August 16
Check-out also moves from noon to 11am from August 16 onward. And two blocks down the road, Arnolds Park Amusement Park thins its schedule through the end of the season and is generally done after Labor Day weekend, so check their calendar rather than ours before you count on the Legend.
What actually runs in any given week late in the season comes down to staffing. The only reliable answer is the one you get on the phone, and it is worth asking before you book rather than after.
What is still running
Both pools, and both are heated. The indoor one is Old Faithful, the first cottage A.T. Fillenwarth built on this shoreline in 1918 and one of only two buildings left standing when the 1968 tornado took the main beach. It was converted into the pool in the 1970s. The outdoor pool is in the middle of Cottage Colony.
The paddle boats, canoes and rowboats sit on the dock with life jackets and paddles and no sign-up sheet, which is exactly what you want when there is no schedule to work around. The docks at Main Beach, North Beach and South Beach are all still yours. So are the tennis court with its pickleball lines, the sand volleyball court and the beaches.
And the Seawalk, which replaced the old 1938 sea wall in 1998, faces west with lounges and gas grills along it. September sunsets off this shoreline are the best of the year and there is nobody on the lawn to share them with.
The lake itself does not wind down at all. If anything it improves. We have set out the water temperature month by month elsewhere, but the short version is that the first ten days of September reach 70°F or better on 86% of days, and boat traffic by then is a fraction of what it is in July.
Who this suits, and who it does not
Here is an opinion, and we are the ones with the dock. If you bring your own boat, the late season is the best value on this lake and it is not close. Tie up at a dock or buoy at no charge, first come first served, and the thing that gets reduced is precisely the thing you did not need. Same for anyone whose holidays are not governed by a school calendar, which is a large share of who we see in September.
It does not suit everybody, and we would rather say so. If your children have spent the year waiting to get up on skis behind one of our boats, come in July and pay July prices. That is what July is for. If you are bringing a group of four or more units, note that the cancellation window is longer for group bookings than for a single small unit, so ask when you call.
For a single unit equipped for six or fewer, cancellations need 30 days’ notice. The deposit is the greater of 20% of the weekly rate or one night, and it exists because we do not overbook. If we hold a unit for you, we have turned somebody else away for it.
FAQ
When are Okoboji rates cheapest?
At Fillenwarth Beach, before June 7 and from August 16 to closing, when rates are half. The shoulder weeks at 25% off are June 7 to 29 and August 9 to 16. Those are the 2026 dates and they shift slightly each year, so check the current brochure.
Is it worth going to Okoboji in September?
If you want the lake, yes. Early September water averages 73°F, warmer than mid-June, and the lake is quiet. If you want the full activity programme, no, because it is not running. It depends entirely on which of those you came for.
Can you book just a weekend at Fillenwarth Beach?
Yes, subject to availability. In July a weekend has to fit between weekly bookings and often cannot. After September 7 it fits easily and there is no weekend premium on the rate.
Does the amusement park stay open in September?
It reduces its schedule through the late season and is generally finished after Labor Day weekend. Check the park’s own calendar before you plan a trip around it, because their season and ours do not end on the same day.
If you are weighing a late-season week or a weekend, call and ask what is actually scheduled. Someone who knows all 38 unit types and what the staffing looks like that particular week will pick up, which is more use than any booking form. Reach us at (712) 332-5646, toll free on (800) 332-7236, or through the reservations page. The 2026 brochure has every unit and every rate in it if you would rather read first and call later.