Southwest Airlines doesn’t have fancy onboard offerings such as first class or economy plus seats, but they do have a unique boarding process where you are assigned a specific boarding number that determines when you can get on the plane. How quickly you get on the plane will directly correlate to whether or not you can claim your desired first-come, first-served seats. Your Southwest boarding assignment will fall in group A, B or C, and you will be assigned a number ranging from 1–60 within that group. Yes, it feels a bit like you are lining up as cattle in order to board the plane but once you get the hang of it, it isn’t that terrible. Or at least, it isn’t terrible if you have a good boarding group number.

At the heart of the Southwest boarding system is the concept that you want to check-in for your flight exactly 24 hours before departure as the boarding assignments are given in the order you check-in. However, like with almost everything in the airline industry, it isn’t truly quite that simple.

The coveted first A 1–15 spots go to those who purchase pricier Business Select Fares or who upgrade to one of those boarding spots on the day of travel at a price of $30–$50 per person. This same-day buy-up option is only available shortly before departure if the A 1–15 slots aren’t already all spoken for by BusinessSelect customers. So, you can’t fully count on this working. However, if you have the Southwest Rapid Rewards Priority Credit Card or Southwest Rapid Rewards Performance Business Credit Card, know that each of those cards comes with four included A 1–15 slots each year (which is why these are some of our favorite Southwest cards for families).

Next, there are those who have Southwest A-List or A-List Preferred elite status who are automatically assigned a boarding number before the T-24 hour mark, so simply checking in exactly at 24 hours before your flight also won’t get you ahead of them either. There is also the issue of those who are already on the plane from a previous segment on a direct routing to their final destination. This is where that subtle but distinct difference between direct and nonstop flights comes into play. Direct simply means you don’t change planes, not that the plane doesn’t stop somewhere along the way. Unless you are on the first flight of the day, there is a reasonable chance some seats on the plane are spoken for by through-passengers before A1 even gets a chance to board.

Now that you understand that even checking in at exactly 24 hours before your first Southwest flight won’t score you one of the very best boarding pass assignments, let’s talk about Southwest EarlyBird Check-In. Southwest offers the EarlyBird Check-In service to automatically check you in 36 hours before your flight, instead of you manually remembering to check-in at 24 hours out.

This serves two obvious purposes. First, it takes out the human element of being too busy or forgetting to check-in exactly 24 hours before your first flight. Second, it scores you a boarding assignment that should be better than those still available at 24 hours out. The closer the boarding pass assignment is to A1, the earlier you board. The earlier you board, the better selection of seats and overhead bins you will have.

This EarlyBird Check-In option now costs up to $25 per person per direction of travel. Originally this was only $10, but the price now varies by flight and represents a real investment if you have multiple people traveling. For our family of four, we would be out up to $200 to use EarlyBird Check-In on a round-trip Southwest journey.

Also know that while Southwest has flexible policies when it comes to changing your flight or even canceling completely to use the credit in the future, the money you spend on EarlyBird Check-In (EBCI) is not refundable. If you cancel your flight, Southwest doesn’t refund your EBCI purchase. If you change your flight at least 25 hours prior to the original flight’s scheduled departure and you are changing to a flight that doesn’t depart for at least 25 hours, then the EBCI should transfer as long as the confirmation number remains the same.

Given all that, is Southwest EarlyBird Check-In worth it? For some people this answer will always be no, either because the exact boarding position isn’t that important to them, it is outside the budget or because they are OK with Family Boarding. Family Boarding is available for children 6 and under, their child siblings and up to two adults. This boarding takes place between the A and B groups. If your family meets that criteria, then you are only helped by having an A boarding pass, but not hurt by having a B or C boarding pass since you will board before then anyway.

If you have the budget to consider EBCI, it might be worth it in a few cases. First, EarlyBird Check-In might be worth it if the flight you are taking is especially long, making seat selection more valuable — such as on a Southwest flight to Hawaii. Second, if it is crucial for your family or group to sit all together, and either you don’t qualify for Family Boarding or you are worried there won’t be seats for all of you still left together at that time, it could be worth it. It may also be worth it if you know you will be too busy at T-24 to check yourself in on time. Last but not least, if having EarlyBird Check-In simply reduces your stress or anxiety about the flight, then that by itself can be worth the cost.

My family occasionally purchase EarlyBird Check-In simply to make the whole process of flying Southwest easier, especially on longer segments. However, we don’t always purchase it because family boarding is often a sufficient time to get seats together since we still have a younger child who qualifies.

Know that you can also choose to purchase EBCI just for a portion of your trip, or even just for certain travelers on the journey. It doesn’t have to be an all or nothing decision.

At $15–$25 per person, Southwest EarlyBird Check-In can be worth the cost, but it won’t always be a slam-dunk deal, especially if Family Boarding is an option for your group. If you fly Southwest with your family, I’d love to hear how you decide if and when Southwest EarlyBird Check-In is worth it for you.

If you do decide to purchase Southwest EarlyBird Check-In, you can earn bonus points from using the right credit card, plus consider picking up a Southwest credit card if your family enjoys traveling the country (and beyond) on Southwest.

This story was originally published on The Points Guy. Sign up for the TPG daily newsletter and wake up to unbeatable flight deals, travel industry news, and credit card bonuses that let you travel first-class to some of the world’s most incredible destinations at a fraction of the price.