Carrier route record
NKDTW→PHL
Spirit Airlines · Detroit to Philadelphia
- Flights
- 132
- Period
- July 2025 to June 2026
- Share of route
- 4%
- Carriers
- 7
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Spirit Airlines.
Spirit on DTW to PHL lands a B+, about a point better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 132 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,557 at 80.1% on time.
The US average over the same twelve months is 77.6%, so there is little to separate Spirit on DTW to PHL from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.8%
Arrivals under 15 minutes late, of 132 completed flights
Avg delay
79 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.81%
Whole route
78.5%
Every carrier on DTW to PHL, 2,952 flights
These figures cover 132 flights between July 2025 and June 2026. Beyond the headline rate, 10.6% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Spirit against every carrier on DTW to PHL
Spirit flew 132 of the 2,952 flights on DTW to PHL, about 4% of it. Its 78.8% on time is about level with the route as a whole at 78.5%. Ranked by on-time rate it is number three of seven carriers on the route, where the range runs from Delta at 80.1% to SkyWest at 61.5%. Four of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: half a point separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 1,557 | 80.1% | 77 min | 2.06% | B |
| PSA Airlines | 846 | 79.5% | 91 min | 5.20% | B− |
| Spirit Airlines (this page)thin sample | 132 | 78.8% | 79 min | 0.00% | B+ |
| Republic Airwaysthin sample | 112 | 73.6% | 88 min | 5.36% | C− |
| American Airlinesthin sample | 179 | 72.3% | 129 min | 0.56% | C+ |
| Frontier Airlinesthin sample | 57 | 69.1% | 55 min | 3.51% | C− |
| SkyWest Airlinesthin sample | 69 | 61.5% | 93 min | 2.90% | D |
PSA Airlines cancels 5.2% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Departure window
When Spirit runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 132 flights.
There are not enough flights in each departure window to split Spirit's DTW to PHL record by time of day without the percentages moving on noise. The headline rate of 78.8% is the reliable figure here.
Across the year
Spirit on DTW to PHL through the year
- Jul–Sep 202581 flights75.3%
- Oct–Dec 202549 flights87.8%
- Apr–Jun 20262 flights—
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 78.8% on time across 132 flights.
Split by quarter, Spirit on DTW to PHL logged 81 flights in Jul–Sep 2025, 49 flights in Oct–Dec 2025 and 2 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 78.8% annual figure is the one to use.
Delay causes
Why Spirit runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 2,201 reported delay minutes.
- 41%National Airspace System
- 33%Late-arriving aircraft
- 26%Carrier
41% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 913 minutes out of 2,201, against a national NAS share of 21%. The split is drawn from 2,201 reported delay minutes.
Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.6% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 453 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8pm–5am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 87.9% on time across 133 flights, 9 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 9 points of difference.
One caution: this is a thin sample. 132 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Spirit on DTW to PHL
Put together: treat all of this as provisional. 132 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 78.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 132 completed flights over 12 months sit behind that.
Related
Where to go next
- DTW to PHL, every carrier
- Spirit on PHL to DTW, the return leg
- Delta Air Lines on DTW to PHL80.1%
- PSA Airlines on DTW to PHL79.5%
- Republic Airways on DTW to PHL73.6%
- American Airlines on DTW to PHL72.3%
- Spirit Airlines network-wide record
- Detroit Metropolitan Wayne County (DTW) delay statistics
- Philadelphia International (PHL) delay statistics
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.