Campsite Sniper
Wyoming · Recreation.gov

Mammoth Campground (Yellowstone)

44.9746° N / 110.6933° W · Data Nov 2 2026, checked hourly
Next open date Apr 16, 2027Next open weekend Apr 16, 202781 monitored sites

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Every site at Mammoth Campground (Yellowstone), colored by availability across the tracked window. Tap a site for its calendar.
Mammoth Campground (Yellowstone)

Pick a site on the map to see its availability calendar.

01 · Detected Opening History · the openings record · file CS-247571

When Mammoth Campground (Yellowstone) reopens

Mammoth Campground (Yellowstone)'s openings record: every site-date Campsite Sniper detected turning available, logged and time-stamped. Refreshed hourly.
Openings · last 7 days
0
Openings · last 30 days
197
Openings · last 90 days
961

Weekday pattern

Detected openings by day of week · 90d
04080120160200131116140179159113123MONTUEWEDTHUFRISATSUNOPENINGS RECORDED · LAST 90 DAYS · N = 961

No strong weekday pattern is evident in the openings Campsite Sniper has detected: 961 openings spread across the week.

Hour-of-day pattern

First detected by hour · local time · last 90 days
0100200300400337000408121620HOUR OF DAY (24H) · MT · LAST 90 DAYS

The largest concentrations of detected openings were first detected during the 06:00 and 11:00 local-time hours. Those hours contained 403 of 961 detected openings (41.9%). Hours show when Campsite Sniper first detected each opening, in Mountain Time, not when the change was made upstream.

Lead-time profile

Days before stay date · percentiles
P25 · 3DMEDIAN · 8 DAYS OUTP75 · 14D0306090120150180DAYS BEFORE STAY DATE

Half of the openings Campsite Sniper detected appeared at least 8 days before the stay date; the middle 50% land 3–14 days out. Set an alert if you want Campsite Sniper to monitor future openings.

Highest-churn sites

Most openings · 90d
SiteOpeningsShare of all openings
Mammoth site #38  232.4%
Mammoth site #2  222.3%
Mammoth site #3  212.2%
Mammoth site #21  212.2%
Mammoth site #29  212.2%

Site Mammoth site #38 had the most detected openings in the last 90 days: 23. One free watch covers every site here.

02 · Availability Outlook · Nov 2, 2026 – May 3, 2027 · of 81 monitored sites

Of the 14,823 tracked site-nights (Nov 2, 2026 – May 3, 2027): 366 open for online reservation · 276 reserved · 6,270 on sites not offered for online reservation (first-come, first-served or administrative) · 7,740 closed · 171 not yet released.

Where the open windows are

97.5% of tracked site-nights are not currently open for online reservation. 366 of 14,823 remain open; here is where they are.

Load status

Nov 2, 2026 – May 3, 2027
Not open online97.5%
Open site-nights366 / 14,823
Reserved (of online inventory)276 / 642
Weekday openings162
Weekend openings204

Of the open site-nights on mapped sites, 162 fall on weekdays and 204 on weekends (Fri–Sun).

Open dates by month

Nov 2026 – May 2027
05001,0001,5002,0002,5000 OPEN0 OPEN0 OPEN0 OPEN0 OPEN250116NOVDECJANFEBMARAPRMAYSOLID = OPEN SITE-NIGHTS · DASHED OUTLINE = TOTAL BOOKABLE

November shows no online availability. 0 of 2,349 tracked site-nights are open there — 1,102 on sites not offered online, 1,247 closed.

Holiday windows

Sites open per night · of 81 sites
WindowNightSites openStatus
ThanksgivingTHU Nov 260None open
FRI Nov 270None open
SAT Nov 280None open
ChristmasTHU Dec 240None open
FRI Dec 250None open
New YearTHU Dec 310None open
FRI Jan 10None open
Memorial DayFRI May 280None open
SAT May 290None open
SUN May 300None open
MON May 310None open

Thanksgiving: no online availability on any tracked night. Christmas: no online availability on any tracked night. New Year: no online availability on any tracked night. Memorial Day: no online availability on any tracked night.

Best-availability sites

Most open site-nights · tracked window
SiteOpen site-nights
Mammoth site #15  18
Mammoth site #19  18
Mammoth site #3  18
Mammoth site #66  18
Mammoth site #68  18

The 5 sites with the most open site-nights in the current snapshot. Pair a bookable date with a free alert to cover everything else.

Next windows

As of Nov 2, 2026 snapshot
Next open dateFri · Apr 16, 2027
Next open weekendFri · Apr 16, 2027
November0 of 2,349 · no online availability

The next bookable night is Apr 16, 2027; the first open weekend starts Apr 16, 2027. Campsite Sniper can watch later dates for you.

Stays and site detail

366 open site-nights across 51 sites at Mammoth Campground (Yellowstone), from the same hourly snapshot as everything above.

Multi-night stays. 54 2-night, 52 3-night, 18 7-night openings where a single site is free for every night, per Campsite Sniper's current snapshot — soonest Apr 16, 2027 at site Mammoth site #15.

RV length. Longest recorded site here is 99 ft. 78 sites take 25 ft, 72 sites take 35 ft, 70 sites take 40 ft.

All 51 sites with current availability
SiteMax RVHookupsOpen site-nightsLongest runDates
Mammoth site #1540 ftNone1818 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +6 more
Mammoth site #1956 ftNone1818 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +6 more
Mammoth site #352 ftNone1818 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +6 more
Mammoth site #6641 ftNone1818 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +6 more
Mammoth site #6845 ftNone1818 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +6 more
Mammoth site #760 ftNone1612 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +4 more
Mammoth site #568 ftNone1515 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +3 more
Mammoth site #660 ftNone1513 nightsApr 16, 2027, Apr 17, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027, Apr 28, 2027, Apr 29, 2027, Apr 30, 2027 +3 more
Mammoth site #962 ftNone1515 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +3 more
Mammoth site #1155 ftNone1413 nightsApr 16, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027, Apr 28, 2027, Apr 29, 2027, Apr 30, 2027, May 1, 2027 +2 more
Mammoth site #6151 ftNone1410 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 30, 2027, May 1, 2027 +2 more
Mammoth site #6560 ftNone1413 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +2 more
Mammoth site #1860 ftNone1313 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027 +1 more
Mammoth site #1253 ftNone1212 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027, Apr 27, 2027
Mammoth site #6060 ftNone1110 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 30, 2027
Mammoth site #1350 ftNone1010 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027
Mammoth site #1737 ftNone1010 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027
Mammoth site #5760 ftNone88 nightsApr 19, 2027, Apr 20, 2027, Apr 21, 2027, Apr 22, 2027, Apr 23, 2027, Apr 24, 2027, Apr 25, 2027, Apr 26, 2027
Mammoth site #2558 ftNone64 nightsApr 16, 2027, Apr 17, 2027, Apr 30, 2027, May 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #5460 ftNone65 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, May 3, 2027
Mammoth site #6265 ftNone66 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027, Apr 21, 2027
Mammoth site #1466 ftNone55 nightsApr 16, 2027, Apr 17, 2027, Apr 18, 2027, Apr 19, 2027, Apr 20, 2027
Mammoth site #2396 ftNone44 nightsApr 30, 2027, May 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #2658 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #2758 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #3099 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #3148 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #3258 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #3361 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #3646 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #3856 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #4057 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #4262 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #4856 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #5055 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #5255 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #5358 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #6933 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7148 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7450 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7548 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7642 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7722 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7820 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #7924 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #8030 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #8150 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #8240 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #8350 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #8546 ftNone33 nightsMay 1, 2027, May 2, 2027, May 3, 2027
Mammoth site #2460 ftNone11 nightApr 30, 2027

About Mammoth Campground (Yellowstone)

Overview

Starting Tuesday April 15th, the Mammoth Campground is open and reservations are required.

For reservations at the campgrounds managed by Yellowstone National Park Lodges (Fishing Bridge RV Park, Bridge Bay, Canyon, Madison, and Grant Village campgrounds), please visit the Yellowstone National Park Lodges Camping website.

Recreation

There are many recreational opportunities in the Mammoth Hot Springs and the North area. Visit these pages to learn more:

Boating

Fishing

Hiking

Photography & Wildlife Watching

Explore the boardwalks above Mammoth Hot Springs to view the the steaming Hydrothermal Features or take a drive around the vibrant travertine terraces.

Explore in Winter. Ski or snowshoe among the whiffs of sulfur along the Upper Terraces.

Explore the historic Fort Yellowstone area.

Visit the park's Mammoth & Hot Springs North web page to learn more.

Facilities

Mammoth Campground offers:

82 campsites Some Cell Phone Reception Food Storage Lockers Trash/Recycling Collection Amphitheater - Seasonal Staff or Volunteer Host On Site - Seasonal Potable Water spigots Flush Toilets - year round

There are no showers at the campground

Natural Features

The Mammoth Campground is in a high sagebrush steppe, scattered juniper and Douglas fir trees provide shade during hot summer months. Wildlife including elk, bison, pronghorn, and mule deer frequent the Mammoth Hot Springs and the North area of the park, depending on the season.

The road from the North Entrance to the Mammoth Campground winds up the Gardner River canyon, past crumbling walls of sandstone and ancient mudflows. The vegetation is much thicker in the canyon than on the open prairie down below, the common trees being Rocky Mountain juniper, cottonwood, and Douglas-fir. Low-growing willows also crowd the river's edge in the flatter, flood-prone sections of the canyon. Watch for wildlife, which varies by the season. Eagles, osprey, dippers, and kingfishers can be spotted along the river, while bighorn sheep climb along the steeper parts of the canyon. Elk are common in Mammoth Hot Springs, while bison can often been seen along the road out to Tower–Roosevelt.

Spring and Fall daytime temperatures range from 30°F (-1°C) to 60°F (15°C) with overnight lows in the teens to single digits. Snow is common in the spring and fall. Summer temperatures are often around 70°F (21°) to 80°F (27°C) and occasionally 90°F (32°F) at lower elevations. Nights are usually cool and temperatures may drop below freezing at higher elevations. Thunderstorms are common in the afternoons. During winter, sub-zero temperatures and snow are common, especially at night and at higher elevations. Winter temperatures range from 0—20°F (-20—-5°C) throughout the day, with sub-zero temperatures overnight.

81 monitored sitesRVs up to 99 ftNo hookups5 shadedPets OKFire pitsMax party 6

Getting there

The Mammoth Campground is located in the Mammoth Hot Springs area in the Northen section of the park, five miles from the park's North Entrance near Gardiner, MT. Visit the park's website for more information including directions and maps: https://www.nps.gov/yell/planyourvisit/directions.htm

Yellowstone National Park, Yellowstone, WY 82190307-344-2107
AmphitheaterAuto TouringBirdingCampingCross Country SkiingCultural ActivitiesFishingHikingHistoric & Cultural SiteInterpretive ProgramsSkiingVisitor CenterWildlife Viewing

View on Recreation.gov ↗   Get directions ↗

FAQ

How do I get a reservation at Mammoth Campground (Yellowstone)?

Reservations for Mammoth Campground (Yellowstone) are made through Recreation.gov. 97.5% of tracked site-nights are not currently open for online reservation; 366 of 14,823 remain open. Campsite Sniper has also detected 961 site openings here in the last 90 days, so further dates may appear. Pick a site on the map to see its calendar, or set a free Campsite Sniper alert. You complete the reservation yourself on Recreation.gov.

Does Campsite Sniper book this campground for me?

No. Campsite Sniper sends alerts and direct Recreation.gov links. It never books, pays for, holds, hoards, or resells reservations.

How current is this availability data?

Campsite Sniper re-checks public Recreation.gov availability for this facility every hour and republishes whenever anything changes. This facility's data last changed at Nov 2, 2026 17:20 UTC; an older timestamp means nothing has changed since that time, not that checking stopped. Always confirm final availability on Recreation.gov when you book.

How often do new openings appear at Mammoth Campground (Yellowstone)?

Campsite Sniper detected 961 site-date openings here over the last 90 days, none in the last 7. A free alert watches around the clock and pings you the moment one appears.

Can I get a multi-night stay at Mammoth Campground (Yellowstone)?

52 three-night openings are showing, counting only runs where the SAME site is free for all three nights. The soonest starts Apr 16, 2027 at site Mammoth site #15. Confirm and book on Recreation.gov.

Which sites at Mammoth Campground (Yellowstone) fit a 35-foot RV?

72 of the 81 sites that support RV analysis have a recorded maximum of 35 ft or more; the longest recorded is 99 ft.

Which month has the most availability at Mammoth Campground (Yellowstone)?

April 2027, with 250 open site-nights in the current snapshot of 2,430.

How far ahead of a stay do openings appear at Mammoth Campground (Yellowstone)?

Half of the openings Campsite Sniper detected appeared at least 8 days before the stay date; the middle 50% landed 3-14 days out. Campsite Sniper can monitor future changes for dates you select.

When is the next open date at Mammoth Campground (Yellowstone)?

As of the Nov 2, 2026 snapshot: the next open date is Fri, Apr 16, 2027 and the next open weekend starts Fri, Apr 16, 2027. Detected openings can add earlier dates at any time; a free Campsite Sniper alert catches those the moment they appear.

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