Thomas Bergmann
Analyst · Morgan Stanley
Great. Thanks, Bahram, and hello, everybody. I'll provide some additional detail on our third quarter and year-to-date results as well as our outlook for the remainder of the year.
In the third quarter, total revenue increased 67% to $385 million, driven by increases in both center and other revenue. Total center revenue increased 63% to $372 million and was driven by increases in both membership dues and in-center revenue. Average center revenue per center membership also rebounded nicely to $555 from $349 in the same prior year period, reflecting increased spending with our in-center businesses, the continued execution of our pricing strategy and the opening of new centers in more affluent markets. On a same-store basis, comparable center sales increased 59%.
Center memberships increased approximately 17% to just over 668,000 as of September 30, 2021, compared to approximately 573,000 as of September 30, 2020. Our third quarter ending center membership balance also reflects a sequential increase of just over 10,000 memberships compared to the end of the second quarter of 2021.
During the third quarter, as Bahram stated, nearly 20% of our clubs in various jurisdictions across the country, including some of our large markets such as Chicago and North Carolina, had mask mandates and other COVID-19-related restrictions imposed on them during the quarter. In light of these restrictions and the typical seasonality in our business during this quarter, we are particularly pleased with the sequential quarterly growth in memberships.
As Bahram shared, we have continued our relentless focus on delivering the very best premium experiences to our members. As we have delivered these premium experiences, we have strategically increased our new join membership prices across most of our centers in early 2021. We believe we can continually refine our pricing as we deliver exceptional experiences and find the optimal balance among the number of memberships per center, the member experience and maximizing our return for each center.
Third quarter average monthly dues per membership of $134 was approximately 10% higher than the average monthly dues per membership of $122 in the third quarter of 2019 and approximately 20% higher than the average monthly dues per membership of $112 in the third quarter of 2020. Important to highlight is that this increase in average monthly dues per membership shows our strategy is working by being able to charge higher new join membership rates and opening new centers in more affluent markets. We believe we also have the opportunity over time to increase legacy member pricing. We are using our experience and data analytics to look at member data and pricing across the portfolio of our clubs, and we expect to continue to raise prices thoughtfully and analytically while minimizing any member attrition. We expect average revenue per membership and average monthly dues per membership to continue to increase as we acquire more new members, increase legacy member pricing and open new centers in increasingly affluent markets.
Other revenue, which includes revenue generated from businesses outside of our centers, increased more than fourfold to $13 million in the quarter and was primarily driven by our athletic events business as we were able to produce several of our iconic events during the third quarter of 2021 compared to the third quarter of 2020 when COVID-19 restrictions forced the cancellation of most of our events.
Moving on to operating expenses. In the third quarter, total operating expenses increased 25.1% to $402.6 million versus the prior year period and included $4.1 million of share-based compensation expense and $2.5 million of nonrecurring items. Center operations expense increased 40% to $232 million and was primarily driven by the reopening of our existing centers and the addition of 7 new centers, partially offset by staffing productivity and other cost efficiency initiatives at our centers. Rent increased 10.5% to $52.5 million, driven primarily by the sale leaseback of 5 centers occurring since Q3 of 2020 and our taking possession of 6 sites for future centers where we started incurring GAAP rent expense, most of which is noncash.
General, administrative and marketing expenses increased 40.7% to $45.3 million, which included $4.1 million of share-based compensation expense and $0.6 million of nonrecurring expenses. This increase is primarily due to the return of corporate team members who remained furloughed during the third quarter of 2020 and an increase in marketing spend with more clubs opened during the third quarter of 2021 compared to the third quarter of 2020. Depreciation and amortization decreased 5.5% to $58 million, and other operating expenses decreased 2.3% to $14.8 million. As a result of our continuing recovery, our operating loss improved 81% to $17.5 million from $90.8 million in the prior year period.
Net interest expense increased to $39.8 million from $31 million in the third quarter last year. This is due to a higher average net debt balance during this year's third quarter. Our third quarter effective tax rate was 20.8% compared with 22.8% in the prior year period. This lower effective tax rate is primarily a result of valuation allowances against our state net operating loss carryforwards.
Net loss was $45.4 million this quarter compared with a net loss of $93.6 million last year, which included tax-effected expenses of $3.2 million related to share-based compensation and $2 million primarily related to a nonrecurring loss on a sale-leaseback of one of our properties.
Finally, as Bahram mentioned, adjusted EBITDA improved significantly to $47 million from a loss of $12.4 million in the third quarter of last year.
Moving on to the balance sheet. Cash and cash equivalents as of September 30, 2021, was $44.8 million compared to $33.2 million as of December 31, 2020. As you all know, we completed our IPO earlier this month, which generated proceeds of approximately $670 million after offering related underwriting discounts and other cost. We used the proceeds to repay $576 million of our senior secured term loan facility, which included a $5.7 million prepayment penalty and added cash to the balance sheet for general corporate purposes.
Additionally, the underwriters in the IPO notified the company yesterday that they were exercising their option to purchase nearly 1.6 million additional shares of common stock at the $18 per share IPO price, which will result in additional net proceeds to the company of approximately $27.2 million after deducting underwriting discounts and commissions. We intend to use the net proceeds for general corporate purposes.
Net capital expenditures totaled $79.8 million during the third quarter compared with $45.6 million in the prior year. The increase is primarily due to a higher number of active new club construction projects and an increase in maintenance capital expenditures compared to last year's third quarter when many of our clubs were just reopened or partially opened during the quarter.
Turning now to our outlook. For Q4 2021, revenue is expected to be in the range of $350 million to $360 million, and adjusted EBITDA is expected to be in the range of $48 million to $52 million. Included in this guidance is the closure of 4 smaller nonpremium, nonbrand right centers where the company has elected to allow the leases to expire. Also underlying this guidance is the assumption that current COVID-19 mask mandates and other related restrictions remain in place for the clubs that are currently under restrictions and do not impact more clubs than are affected today.
With this guidance, we expect our fourth quarter adjusted EBITDA margin to improve compared to the third quarter of 2021 as we continue to see the benefits of staffing and other cost efficiency initiatives, lower insurance and team member benefit costs and lower real estate tax expense.
So before closing, I want to join Bahram in sharing how pleased I am with how well positioned the company is to continue to gain market share as demand for experiences and healthy living continues to grow. With the Life Time brand, our attractive member demographics and our asset-light real estate development model, I believe we are poised for rapid expansion for the foreseeable future and the opportunity to serve and bring healthy living, healthy aging to more and more consumers across North America.
To wrap it up, I want to reiterate Bahram's comments on how proud we are of the extraordinary Life Time team members who continue to deliver an unparalleled healthy way of life experience for our members and advance our strategic priorities.
And with that, I'll turn it back to you, Jessie, to open the call up for questions.