Thank you, Kyle, and thank you, everyone, for joining us on today's call. As Steve and Kyle mentioned, this quarter has been a very strong start to 2021 with the Trinity team. We are very proud of the successful IPO we closed on February 2, where we raised net proceeds of approximately $104 million and the issuance of approximately 8 million shares of our common stock. In addition, we had solid investment activity and portfolio performance, as I will discuss shortly.
I will be focusing my remarks on the following key areas: portfolio growth, operating performance, NAV and return performance, credit performance and liquidity. With that, I will start with portfolio growth.
During the first quarter, we entered into $124 million of new commitments and deployed $87 million across 19 portfolio companies. We funded $61.4 million in secured loans to 8 portfolio companies. We funded $14.7 million in equipment loans to 7 companies, and we received $1 million in warrants in connection with this funding activity. We also invested $10 million in direct equity investments in 4 portfolio companies, including the exercise of our warrant in Atieva.
As a result of the new investment activity, we continued our goal of transitioning the portfolio to floating rate loans as we ended the quarter with approximately 32% of our debt portfolio in floating rate securities. During the second quarter, we received $67 million in principal repayments, of which $40 million were from early debt repayments, which indicates the quality of our borrowers and their ability to raise additional equity capital or move to more conventional bank lenders to repay our debt.
As a result of the $20 million of net investment activity and approximately $7 million of accretive income and realized gains, our portfolio at cost grew by 5.4% to $525 million. On a fair value basis, our portfolio increased from $494 million to $536 million attributed to the increase in costs I just discussed and the $15.5 million of net unrealized appreciation. The increase in net unrealized appreciation of approximately 3.1% was primarily due to valuation changes in our warrant and equity portfolio.
I will now turn to our operating results. On a GAAP basis, we recorded total investment income of $17.3 million, comprised of approximately $16.3 million in interest income and $1 million in fee income. This represents a $2 million increase or a 13% increase over the $15.3 million of total investment income in Q4. The increase was primarily related to the increased weighted average balance of our outstanding debt portfolio and higher income from early loan repayments as compared to the prior quarter. Our effective yield on the portfolio for Q1 was 15.5%, which was increased from 14.5% in the prior quarter, driven by accelerated income from early repayments.
We incurred $4.6 million of interest and amortization of deferred financing costs on our various debt facilities as compared to $4.3 million in Q4 of 2020. Interest expense under our credit facility was lower in Q1 as we paid down our Credit Suisse facility by $90 million with the proceeds from our IPO. This was offset by higher interest expense on our $50 million of convertible notes, which were outstanding for the full quarter of Q1.
Our weighted average cost of debt, including interest and fee amortization, was 7.2%, which increased from the prior quarter due to the higher borrowing costs on the 6% convertible notes and lower debt balance outstanding under our Credit Suisse facility, which has [ delivered ] cost of LIBOR plus 3.25%. We expect the cost of debt to decrease in the future as we borrow under our credit facility to fund future obligations.
Compensation expense was $4 million in Q1 compared to $4.5 million in Q4. The decrease as compared to Q4 2020 was due to lower variable compensation expense offset by higher salary costs incurred in connection with the addition of 6 personnel to the Trinity team during the first quarter.
Professional fees were slightly lower at $647,000 in Q1 compared to $731,000 during Q4. And this decrease was due to lower accounting and valuation fees in Q1.
G&A expense was $808,000 in Q1 compared to $486,000 in Q4. The decrease in G&A -- the increase in G&A expense was primarily driven by higher D&O insurance expense now that we are a public company. We expect G&A expense to increase slightly over Q1 commencing in Q2 as we incur higher rent expense for our new headquarters located in Downtown Phoenix.
As a result of the activity noted previously, net investment income for the quarter was $7.3 million or $0.31 per share. This compares to $5.3 million or $0.29 per share in Q4 2020. The NII per share would have been meaningfully higher quarter-over-quarter, except for the impact of the 8 million shares of common stock issued in connection with our IPO.
During the quarter, we recognized net realized gains of $2.6 million, primarily related to one portfolio company. We recorded net unrealized appreciation of $15.5 million, primarily driven by appreciation in our equity and warrant portfolios. The increase of $5.6 million in our equity investments was principally driven by an increase of $19.2 million in the fair value of our Atieva investment, offset by $12.6 million of depreciation from mark-to-market adjustments in the balance of the equity portfolio and a flip of unrealized appreciation to realized gain of $1 million.
The net appreciation of $8.6 million in our warrant portfolio was primarily driven by a $3.4 million fair value increase in the Matterport warrant. The reversal of $3 million of unrealized appreciation on our Atieva warrant that we exercised in Q1 and $2.2 million of net appreciation from mark-to-market adjustments on the balance of the warrant portfolio.
Net assets increased by $123 million to $362 million at the end of Q1, primarily due to the net proceeds from our IPO, net realized gains and net unrealized appreciation. The NAV per share increased by $0.66 per share to $13.69 from $13.03 at the end of Q4, primarily due to the net realized gains and net unrealized appreciation recognized during the quarter.
Our credit quality remains strong with over 99% of our portfolio performing. The 3 loans that we had on nonaccrual are the same 3 loans we inherited from the acquired portfolio at the beginning of 2020. So we have had no new nonaccruals. Those 3 loans carry a cost basis of $2.3 million and a fair value of $1.4 million.
Turning now to liquidity. Available liquidity as of March 31, 2021, was approximately $108 million, including approximately $36 million in unrestricted cash and cash equivalents and borrowing capacity of $72 million under our credit facility, subject to existing terms and conditions. End-of-period leverage was 61% and our asset coverage ratio was 264%.
Lastly, on March 24, 2021, we declared a cash dividend of $0.28 per share for the first quarter of 2021 that was paid on April 16 and which generated 111% coverage by our GAAP NII earnings for the quarter. We anticipate declaring a dividend for the second quarter of 2021 during June, subject to approval by our Board of Directors.
With that, I will now open the call for questions. Operator?