Statistics Based Strategies for Winning the Enchantments Lottery

Below is a list of posts about the Enchantments Lottery:

Introduction

In previous analyses of the Enchantments Lottery data, I've looked at the probabilities of success and failure for different combinations of application options. I created categories by zone, day of the week, month, and group size. To get caught up on the previous analyses I suggest taking a look at, Advice on Winning the Enchantment's Lottery (2023 Data Update), which summarizes the earlier posts.

Looking at the probabilities for a given category is interesting and can help an applicant make future decisions to hopefully improve their odds. However, I thought it would be way cooler if I could see how an application entry performs in general, taking into account all the factors (date, zone, group size). If I could generate probabilities for different application entries I might optimize the entries within the application to increase the odds of winning a permit.

This article explains:

• how the Enchantments Lottery works,
• why people misunderstand the advanced lottery quotas,
• the method I used for predicting application entry success in the Enchantments Lottery, and;
• how the probabilities generated from those models can help an applicant optimize their application

How the Enchantment Lottery Works

The Enchantment's Lottery randomly selects applications. Each application consists of three entries in order of preference. An individual entry comprises a zone, date, and group size. For example, an application might look like:

1. Core Enchantment Zone, 2024-08-07, 5
2. Colchuck Zone, 2024-07-28, 3
3. Stuart Zone, 2024-09-01, 2

The date is the trip start date. The lottery tries to determine if any permits are available for the provided date of entry. The entries are evaluated independently and if a permit is available the application is awarded a permit. An application cannot be awarded more than one permit. Furthermore, applicants are only allowed to apply once. Applicants cannot even be alternative permit holders on multiple applications. As a side note, I discussed a strategy of having multiple people in your group apply, and the risks involved, in a previous article titled, Another Way to Improve Your Chances In the Enchantments Lottery.

Zone Quotas

The lottery doesn't evaluate all zones the same. Each zone has its quota restrictions, and the Core Enchantment Zone quota is determined by people, not by group. As of 2024, the quotas are below:

• Core Enchantment Zone: 24 people per day*
• Colchuck Zone: 3 groups per day
• Stuart Zone: 4 groups per day
• Snow Zone: 5 groups per day
• Eightmile / Caroline Zone: 3 groups per day

Unfortunately, these quotas are confusing because the advanced lottery operates differently in conjunction with the daily walk-up lottery.

Daily Walk-Up Lottery

The forest service runs a daily walk-up lottery during the season (May 15-Oct. 31):

"[...] only one permit per zone is issued for the Colchuck, Stuart, Snow Lakes, and Eightmile/Caroline zones and 8 people allotted for the Core Enchantment Zone [...]"

Consequently, the daily permit quotas (advanced lottery + daily walk-up lottery) are one more than listed for all zones (except the Core Enchantment Zone because they included both the advanced lottery quota and the daily quota for the Core Enchantment Zone on their website):

• Core Enchantment Zone: 24 people per day*
• Colchuck Zone: 4 groups per day
• Stuart Zone: 5 groups per day
• Snow Zone: 6 groups per day
• Eightmile / Caroline Zone: 4 groups per day

This is a big deal. If the reader is familiar with the previous analyses, they know Sunday is by far the best day of the week to apply for permits. This is due to the fact the forest service releases the daily walk-up lottery quota in the advanced lottery because no walk-up lottery is held on Sundays during the season. Below is the advanced lottery quota by day of the week for the Core Enchantment Zone:

• Monday-Saturday: 16 people
• Sunday: 24 people

We can do the same for each of the other zones. Add one to the advanced lottery quota for Sunday.

In 2024, the forest service started releasing the daily walk-lottery inventory with the advanced lottery inventory on Sunday and Monday due to no daily walk-lottery held those days. Therefore, we can expect to see increased levels of success on Sunday and Monday moving forward.

The reader doesn't need to keep all these numbers and zones in their head. They simply must understand the advanced lottery is not the same for different days of the week due to quotas and the daily walk-up lottery.

Modeling Application Entry Success

I modeled application lottery success using a collection of logistic regression models fit for each zone. Logistic regression models use a set of variables (known as features) to determine the likelihood of success or failure (binary outcome).

The models use feature coefficients to calculate a probability. If the probability is above 50%, it predicts success, and if the probability is below 50%, the model predicts failure. I don't want to go into the details of how well these models performed based on "F1" scores, precision, recall, and odds ratios in this article. Curious readers can look at the analysis on Github.

However, I want to say these models didn't do great at predicting application entry success or failure on the test data, but all the models had F1 scores of 0.50-0.60. Regardless, given the context, I think the models, odds ratios, and probabilities are valuable. In the rest of this article, I'll explain why the models are valuable and how to utilize them.

Predicting Enchantment Lottery Application Success

Using the function application probability I can enter an:

• Entry date
• Zone
• Group Size
• Processing Sequence

The function returns the calculated probability of being awarded a permit.

application_probability('2025-07-27', 'Colchuck Zone', 4, 2000, log=True)
# 0.09633555979800026

Processing Sequence

The processing sequence is the order the application was evaluated in the lottery. In other words, an application with a processing sequence value of 1 means the application was the first to have a chance at winning a permit. The models would be horrendous at predicting awarded permit values if there was no processing sequence column.

Typically, when the forest service provides Enchantments Lottery data on their website, the processing sequence is not included. Surprisingly, the forest service published the raw data in PDF format for 2023. It was a bit inconvenient, but after realizing the additional data in the PDF the time spent parsing the document was worth it.

The ability to give the models the processing sequence is where most of the predictability power comes from. Examine these two application entries with different processing sequence numbers and their respective probabilities.

application_probability('2025-06-07', 'Core Enchantment Zone', 1, 2000)
# 0.17237437047750997

application_probability('2025-06-07', 'Core Enchantment Zone', 1, 5000)
# 0.00007281371080709937

The only difference is the second has a processing sequence 2.5 times greater than the first, and the probability of success becomes essentially 0%. However, the effect isn't the same for all zones. Take a look at the Snow Zone, instead of the Core Enchantment Zone.

application_probability('2025-08-27', 'Snow Zone', 2,  10000, log=True)
# 0.12208000340982218

application_probability('2025-08-27', 'Snow Zone',  2, 20000, log=True)
# 0.011189258998293993

The processing sequence value is the most important piece of data in the models. The zone, date, and group size values help to optimize the probability of an entry being successful. The processing sequence value helps to optimize whether an application is successful.

Strategies When Applying for an Enchantments Permit

"While permits may be reserved as early as May 15, early spring snow and weather conditions may not allow road access to the Stuart Lake or Eightmile Lake trailheads during the early part of the season. Even if road access is possible, traveling and camping on snow is highly likely during May, June, late September and October."

Okanogan-Wenatchee NFS Website

Some people are only comfortable backpacking if the conditions are perfect in August. Additionally, they aren't interested in zones other than Colchuck or the Core. Those people bet on their application being selected extremely early and one of their low-probability entries finding a way to win them a dream permit. Those people may also find their applications getting rejected year after year. Regardless, it's not a bad strategy. If you're familiar with golf terminology, I have respect for people who refuse to 'lay up'.

On the other hand, some people accept the poor odds and don't even consider the Core Enchantment Zone because they think there is no way they will get lucky and what they want is just to backpack in the Enchantments. Finally, the rest don't know what they want or don't know what they're doing. In the final part of this article, I'll offer an alternative to every one of these groups.

Stratifying Enchantment Entries to Improve Chances of Winning

"No Laying Up"

First, I'll address how an applicant can spread their three entries out when they are only interested in the Core and Colchuck Zones during August.

Group Size

The group size matters in the Core Zone. For example, on Friday, August 1, 2025, if our processing sequence is 500 and our group size is 4, the entry has a 35% chance of winning. If, however, the applicant excludes a few friends and goes with a group size of 2, everything else being equal, the probability of success increases to 43%. Are your two friends worth 8%? If the applicant wants to go solo and selects a group size of 1 the probability increases to 56%.

A few things to consider when selecting group size for the Core Enchantments is how difficult it is to get to. Is everyone you're inviting on this dream trip committed and physically ready for the challenges?

Day of the Week

If an applicant only backpacks on the weekends, they are stuck with Thursday and Friday start days. If they have more flexibility they can utilize different days of the week to improve their odds. Below are the odds for the day of the week for the first week of August in 2025 for the Core Enchantment Zone with a group size of 2 and processing sequence of 500:

• Fri., August 1: 42.81%
• Sat., August 2: 45.63%
• Sun., August 3: 70.27%
• Mon., August 4: 51.91%
• Tue., August 5: 59.17%
• Wed., August 6: 54.98%
• Thur., August 7: 41.20%

Personally, if I wanted to win, I would only choose Sundays, selecting the first three Sundays for each entry in my application. Although moving forward, with no walk-up lottery on Monday, one could argue Monday will be a good option, too. We won't know until we see data from 2024.

One of the odd discoveries in previous analyses is how popular Monday has been. I would stay away from it if I were trying to go during the week and choose a Tuesday or Wednesday instead.

Zone

I've argued previously that the Colchuck Zone is preferable to the Core Zone. The lake is great for swimming, there's fishing, the views are incredible, and a backpacker can day hike up to the Core Enchantments, saving themselves the struggle and dangers of climbing up Aasgard Pass into the Core Enchantment Zone with a heavy pack on. Unfortunately, I'm not the only one who thinks this. The Colchuck Zone is almost as competitive as the Core Enchantment Zone.

In 2023, if an applicant applied for a Colchuck Zone permit, they had a 2.61% of winning a permit. Comparatively, if an applicant applied for a Core Enchantment Zone permit, they had a 2.22% chance of winning. That should surprise many people who think the Colchuck Zone is a great alternative to the Core Enchantment Zone. Let's look at the odds of winning a Colchuck Zone permit for the first week of August (remember group size doesn't matter for the Colchuck Zone). The bold percentages are for the Colchuck Zone and the percentages in (parentheses) are for the Core Enchantment Zone with a group size of 2, everything else being equal:

• Fri., August 1: 36.35% (42.81%)
• Sat., August 2: 54.53% (45.63%)
• Sun., August 3: 77.74% (70.27%)
• Mon., August 4: 57.14% (51.91%)
• Tue., August 5: 66.57% (59.17%)
• Wed., August 6: 67.93% (54.98%)
• Thur., August 7: 54.53% (41.20%)

The Colchuck Zone is, technically, a better alternative than the Core Enchantment Zone with a group size of 2 for most of the days: except Friday. The models I fit predict a person has a better chance of winning a Core Enchantment Zone permit with a group size of 2 on Fridays than they do winning a Colchuck Zone Permit. Remember, the Core Enchantment Zone percentages rise or fall depending on group size, and depending on an applicant's group size, the Core Enchantment Zone might be a better pick than the Colchuck Zone.

Processing Sequence

Even when the applicant is betting on an early selection they can use the processing sequence to increase their chances of winning. Core and Colchuck permits almost completely dry up in the first 10,000 applications (later, I'll create an application that spans the full range of the processing sequence values).

• 91% of Core Enchantment Zone permits were awarded in the first 5,000 applications
• 93.5% of Colchuck Zone permits were awarded in the first 10,000 applications

Consequently, I'll suggest an application looking at how to increase one's chance across this range of processing sequence values. Below are three entries that could do that:

• Entry 1: Core Enchantment Zone, Friday, August 15, Group Size: 4
• Entry 2: Core Enchantment Zone, Sunday, August 17, Group Size: 2
• Entry 3: Colchuck Zone, Sunday, August 17, Group Size: 4

The first entry is the moon shot. Even if our application is selected in the first 2,000 applications there is a small chance of success that drops off steeply until the probability approaches zero around a processing sequence value of 2,000.

The second entry isn't much better than the first but I took two important steps to increase the chances:

• Move the start date to Sunday
• Decrease the group size to 2

The probability of success early in the lottery for the second entry is higher compared to the first entry chart, but the chances drop off quickly when the processing sequence reaches 3,000.

The third entry attempts to extend the chances of winning through the first 10,000 processing sequence values. This is done by changing the zone to the Colchuck Zone. Not only does this raise the odds in the first 5,000 processing sequence values, but it also gives the application a chance if the processing sequence is between 5,000-10,000.

I've said it already in this article but the lottery has changed. Theoretically, good odds are available on Monday now as well as Sunday with the increased permit availability in the advanced lottery.

Next, instead of betting on a lucky draw, I want to examine an application entry set that gives an applicant a chance at winning no matter the processing sequence value.

"Stratification"

The goal of the stratification method is to create probability layers (on a chart) that nicely stack with each application entry. I attempted this with the "No Laying Up" strategy but with less success due to the tight window of processing sequence values. The "Stratification" method requires more flexibility from the applicant. The applicant should be flexible with the time of year and zone.

Even though the applicant needs to be flexible, the picks are still reasonable and offer opportunities to have a wonderful Enchantments trip. Below are the three choices (group size won't matter for these selections):

• Entry 1: Colchuck Zone, Sunday, July 27
• Entry 2: Stuart Zone, Sunday, August 24
• Entry 3: Snow Zone, Wednesday, October 1

The first entry seeks to take advantage if the applicant is lucky with the processing sequence draw. The odds were increased by selecting July and a Sunday entry date. Early in the article, I mentioned why someone might prefer the Colchuck Zone to the Core Enchantment Zone. Additionally, going in late July means snow should not be an issue (hopefully), and going on a Sunday means a backpacker would avoid insane crowds on subsequent days of the trip. For example, if they decide to day hike to the Core on the first full day—Monday—it should be less busy. However, being the Colchuck Zone, the probability of being awarded outside the first 10,000 applications is low.

The second option takes the backpacker away from the mess and noise of the Colchuck and Core zones to the serenity of Stuart Lake. Selecting the Stuart Zone gives our application an increased chance of winning. So much so that, after being sure to choose a Sunday entry date, the applicant can try to get a permit during peak season (Aug. 24). This entry gives the application a chance of winning through the first 30,000 processing sequence values.

I went on a two-night backpacking trip to Stuart Lake the first week of September (2024) and it was one of the best trips I've been on. We found a perfect site allowing us to enjoy privacy, see wildlife, and take in views of the lake and Mt. Stuart. From Stuart Lake, we went on day trips to Colchuck Lake and Horseshoe Lake.

Horseshoe Lake was a gem, and hardly anyone goes up there (the trail is difficult). It felt like we had a slice of the Enchantments all to ourselves.

A day hike to the Core Enchantment Zone from the Stuart Zone would be a very long and difficult day. My uncle made it up to the top of Aasgard on our trip during our day hike, but going any further meant we would have hiked back to Stuart Lake in the dark. Still, the day hike to Colchuck was fantastic and we enjoyed fishing, swimming, and reading by the lake. Don't sleep on the Stuart Zone.

The third entry in the "Stratification" strategy is a bit riskier. Choosing a trip in early October could mean cold temperatures, snow, and a canceled trip. On the other hand, the Pacific Northwest has had some very warm starts to October. The applicant could get lucky and have beautiful weather with a chance to see some larches.

The Snow Zone is another gateway to the Core Enchantment Zone, which means an applicant could day hike to the Core Enchantment Zone from the Snow Zone. The big differences between the Snow Zone and Colchuck Zone are:

• The hike to Colchuck Lake is easier.
• Entering the Core Enchantment Zone from Aasgard Pass (via the Colchuck Zone) involves less hiking and scrambling on rock faces.
• Colchuck Lake is more scenic than Snow Lake.

The Snow Zone has a few advantages over the Colchuck Zone:

• More options for camping
• The road to the Colchuck & Stuart Lake parking lot is notoriously messy and closes later in the season. Conversely, the road to the Snow Lakes trailhead (Icicle Rd.) is easier to drive on and generally stays open.
• Snow Zone permits are less competitive than Colchuck Zone permits

If the applicant is willing to take a risk to increase their chances of winning the Enchantments Lottery they can choose an early October trip to the Snow Zone. If they do, their chances of winning with the third entry should extend through the entire range of processing sequence values.

Taking a look at these three application entry plots we can see the probability layers each entry provides.

Conclusion

It was a lot of fun to build, evaluate, and explore the models and subsequent probabilities. There is room for improvement in the models based on the time of month. For example, a Friday at the beginning of October is not the same as a Friday at the end of October.

The Enchantments Lottery and peoples' behavior change year to year. Some days will, oddly enough, outperform other days for whatever reason. Sometimes the reason is clear, like if there is no walk-up lottery for Sunday or Monday. Other times, it's harder to explain, like why Wednesday outperformed Monday.

My last word of advance to any would-be applicants. Many awarded applications (hundreds) go unclaimed or unconfirmed and are released back into the system when permit reservations become open to the public. This typically happens sometime in April. If an applicant was unsuccessful in the lottery they may have a better chance of fast-clicking their way to success later.