Those and other risks are described in the company's filings with the Securities and Exchange Commission over the past 12 months.
I'm pleased to report that for the quarter, Group 1 generated adjusted net income of $178 million.
This equates to adjusted earnings per share of $9.62 per diluted share, an increase of 38% over the prior year, and an increase of 219% over the pre-pandemic third quarter of 2019.
Our adjusted results exclude non-core items totaling approximately $5 million of net after-tax losses.
As of September 30, we have 2,700 U.S. new vehicle inventory units in stock, representing a 11-day supply.
Our used inventory situation is much stronger at 10,000 units and a 25-day supply.
Our U.S. markets saw 15.5% increase in after-sales revenues versus the prior year.
And we're proud to report that we generated an all-time record quarterly profit in the third quarter of 2021.
Our U.S. adjusted SG&A as a percentage of gross profit was 57.6%.
The UK was 64.6%, and Brazil came in at a record 60.9%.
As Earl mentioned, U.S. new vehicle inventory levels finished the quarter at 2,700 units and a 11-day supply.
Our September inventory receipts were the lowest of the year at approximately 6,800 units.
Our Same Store used vehicle retail unit sales improved by 15% versus the third quarter of 2020.
Our customer pay continues to ramp-up following a very strong first half of the year with 19% same-store dealership gross profit growth compared to the third quarter of 2019.
This allowed us to grow same-store dealership after sales gross profits by 9%, despite continued headwinds in warranty and collision, both of which we believe will reverse in time.
Our third quarter adjusted SG&A as a percentage of gross profit was 67.6%, down from 59% in the third quarter of 2020, and down from 70.5% in the pre-pandemic third quarter of 2019.
In the third quarter, we sold 5,200 vehicles to AcceleRide, a 68% increase over last year.
In the third quarter, 75% of AcceleRide buyers were new to Group 1.
Customers clearly value the superior omni-channel experience that AcceleRide provides which gives Group 1 another avenue to grow incrementally.
Of the customers who placed orders online last quarter nearly 50% uploaded a driver's license and 25% uploaded proof of insurance.
An additional 36% of the orders had a completed credit application as well.
During the quarter, we purchased nearly 5,000 used vehicles from customers through AcceleRide either through trades or through individual acquisitions.
That's up 30% sequentially from the second quarter.
A differentiator for us is our ability to digitally pay customers through Zelle, nearly 1,000 customers out of our 5,000 total took advantage of the digital payment feature in AcceleRide.
In September, we activated integrated delivery fees at 38 dealerships, preliminary results are encouraging.
About 13% of customers chose delivery up front, and so far 5% are confirming in the final steps.
The average delivery distance is 164 miles, further demonstrating our ability to extend our reach with AcceleRide.
Turning quickly to Brazil, despite a nearly 30% decline in industry units sold versus the third quarter of 2019.
As of September 30, we had $297 million of cash on hand, and another $335 million invested in our floorplan offset accounts, bringing total cash liquidity to $632 million.
There was also $282 million of additional borrowing capacity on our U.S. syndicated acquisition line, bringing total immediate liquidity to $914 million.
Subsequent to quarter-end, we issued $200 million of bonds as an add-on to our existing 4% notes to 2028.
We also plan on raising approximately $180 million in mortgage debt to help fund the deal and provide future liquidity flexibility.
We generated $234 million of adjusted operating cash flow in the third quarter and $210 million of free cash flow after backing out $24 million of capital expenditure.
This brings our September year-to-date free cash flow to $522 million, which is allowed us to fund the majority of our Prime acquisition with access cash on hand.
Our rent-adjusted leverage ratio, as defined by our U.S. syndicated credit facility was reduced to 1.5 times at the end of September.
Our leverage was 0.9 times at September 30.
Finally, related to interest expense, our quarterly floorplan interest of $4.8 million was a decrease of $3.3 million or 41% from prior year, due to lower vehicle inventory holdings.
Non-floorplan interest expense decreased $1.5 million or 10% from prior year, primarily due to last year's bond debt refinancing.
Once closed our 2021 Total acquired revenues will equal $2.5 billion.

Summary:
This equates to adjusted earnings per share of $9.62 per diluted share, an increase of 38% over the prior year, and an increase of 219% over the pre-pandemic third quarter of 2019.
And we're proud to report that we generated an all-time record quarterly profit in the third quarter of 2021.