在美国，抵押贷款市场正在萎缩。抵押贷款债务占住房总值的比例降至60年来最低。30年期抵押贷款利率从2021年初的2.7%升至6.2%，高利率导致“锁定效应”，据联邦住房金融局（FHFA）数据，2022年中至2024年中房屋销量减少了170万套。同时，优质借款人（信用评分760及以上）占新增贷款比例已超过三分之二，远高于20年前的水平。

导致市场萎缩的不仅仅是利率上升，更有利于借款人保护但限制较多的监管措施。例如，信贷标准过度严格，尤其针对低于平均水平的贷款额度和灵活就业者。贷款人费用被设定上限，贷款变得缺乏利润，导致许多中低收入家庭无法获得贷款。小额贷款（低于10万美元）几乎无法发放，就连信用社也呼吁放宽相关规定。联邦及州层面有利房主的规定也使得止赎流程显著延长，如今收回抵押房产平均需608天，而2007年不足200天；纽约州甚至超过五年。

为应对市场干涸，特朗普政府提出多项改革，包括50年期和可携带（portable）抵押贷款。超长期贷款会加重借贷人负担，进一步加剧锁定效果。相比之下，可携带抵押贷款便于房主迁徙，有助于缓解因高利率造成的流动性下降。整体来看，金融危机后制定的严格政策在保障系统时也伤害了信用一般的普通家庭，当前应适时修正市场障碍，重振美国抵押贷款市场。

The American mortgage market is shrinking, with mortgage debt as a share of housing stock at a 60-year low. The 30-year mortgage rate rose from 2.7% in early 2021 to 6.2%, and this “lock-in effect” decreased house sales by 1.7 million between mid-2022 and mid-2024, according to the Federal Housing Finance Agency (FHFA). Lending is increasingly limited to high-credit borrowers, with those having scores of 760 and above now making up two-thirds of new loans—more than double the share of two decades ago.

Shrinking activity stems not only from higher rates, but also from stringent post-crisis regulations. Onerous standards especially hurt low- and moderate-income borrowers, freelancers, and those seeking smaller loans under $100,000. Lending profits are slim due to capped fees, making it unappealing for lenders. Even credit unions are demanding rule changes as small loans have become nearly unattainable. At the same time, pro-borrower rules have pushed average foreclosure timelines to 608 days—up from less than 200 days in 2007—and can exceed five years in states like New York.

The Trump administration’s proposed reforms include 50-year mortgages and portable loans. While ultra-long loans risk prolonging debt and worsening lock-in, portable mortgages—which allow balances to move with homeowners—could aid household mobility restricted by higher rates. Ultimately, restrictive post-crisis policies have hurt average borrowers more than they have improved financial stability; the current situation underscores the need to fix regulatory barriers and revive the US mortgage market.