Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands		Dec. 31, 2025	Dec. 31, 2024
Other assets at fair value		$ 138,582	$ 51,358
Accrued expenses and other liabilities at fair value		$ 15,219	$ 15,883
Common stock, par value (in dollars per share)		$ 0.0001	$ 0.0001
Common stock, authorized (in shares)		700,000,000	700,000,000
Common stock, issued (in shares)		98,033,361	93,469,721
Common stock, outstanding (in shares)		98,033,361	93,469,721
Loans held in consolidated securitization		$ 53,800	$ 102,900
Assets
Cash and cash equivalents		652,388	788,422
Restricted cash		404,624	187,841
Loans (at fair value)	[1]	984,552	806,304
Other assets (includes $1,864 and $225 at fair value as of December 31, 2024 and December 31, 2025, respectively)		255,387	160,494
Total assets	[2]	2,974,805	2,366,958
Liabilities
Payable to investors		107,659	60,173
Borrowings		1,829,145	1,402,168
Payable to securitization note holders (at fair value)		46,542	87,321
Accrued expenses and other liabilities		171,495	133,800
Total liabilities	[2]	2,175,990	1,733,740
Total stockholders’ equity		798,815	633,218
Variable Interest Entity, Primary Beneficiary
Other assets at fair value		225	1,864
Assets
Cash and cash equivalents		1,183	1,312
Restricted cash		89,088	47,642
Loans (at fair value)		819,344	750,184
Other assets (includes $1,864 and $225 at fair value as of December 31, 2024 and December 31, 2025, respectively)		6,340	12,971
Total assets		915,955	812,109
Liabilities
Payable to investors		154	154
Borrowings		97,333	195,606
Payable to securitization note holders (at fair value)		46,542	87,321
Accrued expenses and other liabilities		23,415	4,493
Total liabilities		167,444	287,574
Total stockholders’ equity		$ 748,511	$ 524,535

[1] Includes $102.9 million and $53.8 million of loans, at fair value, contributed as collateral for the consolidated securitization as of December 31, 2024 and 2025, respectively. Refer to “Note 5. Fair Value Measurement” for details.

[2] The following table presents information on assets and liabilities related to variable interest entities (“VIEs”) that are consolidated by Upstart Holdings, Inc. at December 31, 2024 and 2025, respectively. The liabilities of each VIE can only be settled using the assets of the corresponding VIE and creditors of these entities do not have recourse to the general credit of Upstart Holdings, Inc. The assets and liabilities in the table below exclude intercompany balances that eliminate in consolidation. December 31,December 31,20242025Assets Cash and cash equivalents $1,312 $1,183 Restricted cash47,642 89,088 Loans (at fair value)750,184 819,344  Other assets (includes $1,864 and $225 at fair value as of December 31, 2024 and December 31, 2025, respectively) 12,971 6,340 Total assets$812,109 $915,955 LiabilitiesPayable to investors$154 $154 Borrowings195,606 97,333 Payable to securitization note holders (at fair value)87,321 46,542 Accrued expenses and other liabilities4,493 23,415 Total liabilities287,574 167,444 Total net assets$524,535 $748,511