How a Little Math and ExpertFlyer Scored us Upgrades to SFO!

Monica and I are heading to California this evening for a quick weekend getaway. As usual, we are flying Delta, having taken advantage of the Delta Companion Certificate issued from my Delta Platinum American Express – score! As far as upgrades go, MSP-SFO is a pretty hard route, especially on a Friday. Originally we were booked on a 5:45pm flight, and had pretty good seats in Comfort+. As the departure date approached, I watched the number of first class seats drop until there was just available as of check-in time.

Enter, ExperFlyer

How did I know there was only one seat? There are a couple of ways to check. One is to use Delta’s app, and tap on ‘Upgrade/Standby List’ to see available Comfort+ and First Class seats. But my favorite way to check is to use a tool called ExpertFlyer.

ExpertFlyer is a service that lets you see all sorts of interesting data about flights. You can view seat maps, on time performance, and most importantly fare class availability.

A quick aside: While Delta sells tickets in ‘Main Cabin’, ‘Comfort+’ and ‘First Class’, they actually split this space into various ‘buckets’ that have a letter assigned to them. For example, a Main Cabin ticket can be sold in buckets Y, B, M, H, Q, K, L, U, T, X & V. These buckets typically are ranked in order of availability and price. That is to say a ‘Y’ fare will likely be more expensive than a ‘V’ fare, but will also likely be more available. As seats are purchased, all buckets decrease by one seat, and some buckets end up with zero seats available.

With this knowledge, one can get an idea of what the upgrade odds look like on Delta for particular flights. Delta allows passengers with Gold or higher Medallion status to ‘same day change’ into another flight, as long as there is availability in the fare bucket.

My Process

As I checked into my original flight, I decided to check what availability on other MSP-SFO flights looked like for today. I ran a quick search in ExpertFlyer and found the following:

Screenshot of showing flight availability for MSP-SFO flights.

Looking at my original flight (DL1505), you can see the first five buckets (J, C, D, I & Z) all showed one seat. These are the first class buckets, and indicate there was only one seat available.

The next bucket, ‘W’, shows zero. W is the Comfort+ bucket, and the fact it was full meant there was a plane-full of folks with elite status occupying all the Comfort+ seats. As a result, I would likely be up against lots of other Platinum and Diamond Medallion members. This was confirmed by looking at the upgrade list and finding Monica and me at 10th and 11th place for that one seat!

But now take a look at DL1839. First off, we can see five seats available in the first class buckets, which is a good sign there’s seats available for upgrades. But even better, the ‘W’ (Comfort+) bucket shows nine seats! ExpertFlyer only shows up to nine seats of availability, so any time you see ‘9’ its likely there are even more than nine seats of availability. Having a pretty empty Comfort+ cabin meant Monica and I would likely not face much competition from elites, as any elites that are on the flight would already have been upgraded to C+ or First Class (other than silver medallions, but they have a lower priority anyway). In addition, there was availability in the ‘V’ economy class, which meant we could do a same day change (we were in ‘V’ class on our original flight).

A quick tweet to Delta got us switched to this earlier flight. Note it costs $75 for non-medallion and Silver Medallion members to switch, but it never hurts to ask if they will waive that fee. Shortly after the switch was made, I logged into the Delta app and…

Screenshot of Delta app showing first class confirmed upgrade on our new flight.

Voila – we were instantly upgraded to first class!

Conclusions + My Advice

This was a pretty sweet win, and meant Monica and I will both enjoy over three and a half hours in a cushy seat, free drinks and a dinner service on tonight’s flight. Upgrades on this flight cost at a minimum $180, so we just saved $360 (and likely more based on demand)!

This strategy of course requires flexibility in your travel plans, but if you have that flexibility its definitely worth it. A few tips:

  • Remember, high availability in the W bucket paired with high availability in the J C D I & Z buckets means you have a good shot at an upgrade.
  • There must be space in your original fare bucket (which will be displayed on your receipt) on the new flight to do a same day change.
  • Look at the seat map of the flight you are switching to to ensure you have a good ‘backup’ seat, and make sure it isn’t delayed.

You can subscribe to ExpertFlyer for $9.99/month, and I think its more than worth it! However, if you are looking for a free alternative, BCD Travel offers a fare bucket search that works just as well, but is a little slower and harder to navigate.

What questions do you have about searching for an upgrade? Leave a comment below!

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