美國國稅局宣布2026年第一季度利率

美國國稅局（IRS）已正式公布2026 年第一季（1 月 1 日至 3 月 31 日）的適用利率。這些利率會影響納稅人的退稅利息、未繳稅款利息、大型企業的利息計算等，對個人與企業的財務規劃都非常重要。

以下整理 2026 年第一季最關鍵的 IRS 利率變動。

一、個人與企業的退款利率（Overpayment Rate）

1. 個人退款利率：7%

當納稅人在某一年度多繳稅款而可獲得退款時，IRS 會支付利息。
2026 年 1–3 月的退款利率為 7%。

2. 公司退款利率（一般）：6%

企業若有多繳稅款，也可以得到利息，利率為 6%。

3. 公司退款超過 10,000 美元的部分：4.5%

如果公司退款金額很大，超過一萬美元的部分，其利率會下降到 4.5%。

二、未繳稅款的利率（Underpayment Rate）

1. 一般未繳稅款：7%

若納稅人未按時繳稅，IRS 會按 7% 計算利息，直到全數繳清為止。

2. 大型企業未繳稅款：9%

大型企業（Large Corporations）如果有遲繳稅款，會適用更高利率，2026 年第一季為 9%。

三、總結

根據 IRS公布的資料，2026年1月至3月的利率如下：

• 個人退款利率：7%
• 一般公司退款利率：6%
• 超過 10,000 美元的公司退款利率：4.5%
• 未繳稅款利率：7%
• 大型企業未繳稅款利率：9%

若您正在處理 2025 稅季或準備 2026 的報稅，了解這些利率能幫助您計算可能的利息、延遲付款成本、以及準備更完整的稅務規劃。

美國註冊會計師 羅霞 提醒您未繳稅款利率偏高（7%～9%），代表晚繳稅的成本容易快速累積，納稅人需謹慎規劃付款時間。務必諮詢專業合格的CPA，以

確保稅務規劃正確，避免因高額利息增加成本。

如果有其他疑問或者需要更多的幫助，

歡迎來電諮詢美國註冊會計師 羅霞 +886 980919600 
或者 E-mail: ustaxproservice@gmail.com 
也歡迎造訪我公司官網: https://www.ustaxproservice.com
(美稅服務有限公司 USTAX Service LLC)

The Internal Revenue Service (IRS) has officially released the interest rates that will apply for the first quarter of 2026, covering the period from January 1 to March 31. These rates affect refund interest, interest on unpaid taxes, and interest calculations for large corporations. Understanding these rates is essential for both individual taxpayers and businesses as part of their financial and tax planning.

Below is a summary of the key IRS interest rate changes for Q1 2026.

1. Overpayment Rates for Individuals and Businesses

(1) Individual Overpayment Rate: 7%

When taxpayers overpay their taxes and are entitled to a refund, the IRS pays interest on the overpaid amount.
For January through March 2026, the individual overpayment rate is 7%.

(2)Corporate Overpayment Rate (General): 6%

Businesses that overpay their taxes may also receive interest from the IRS, with a general corporate overpayment rate of 6%.

(3) Corporate Overpayment Over $10,000: 4.5%

For corporations receiving refunds exceeding $10,000, the portion above $10,000 will be paid interest at a reduced rate of 4.5%.

2. Underpayment Rates (Interest on Unpaid Taxes)

(1) General Underpayment Rate: 7%

If a taxpayer fails to pay taxes on time, the IRS charges interest at 7% until the full balance is paid.

(2) Large Corporate Underpayment Rate: 9%

Large corporations that underpay their taxes are subject to a higher interest rate. The underpayment rate for Q1 2026 is 9%.

3. Summary of Q1 2026 IRS Interest Rates

According to the IRS announcement, the interest rates for January through March 2026 are as follows:

• Individual overpayment rate: 7%
• General corporate overpayment rate: 6%
• Corporate overpayment exceeding $10,000: 4.5%
• Underpayment rate: 7%
• Large corporate underpayment rate: 9%

If you are currently preparing your 2025 tax filings or planning for the 2026 tax season, understanding these interest rates can help you estimate potential interest charges, avoid unnecessary penalties, and strengthen your overall tax strategy.

USCPA Luo Xia reminds you that underpayment interest rates are significantly high (7%–9%), meaning the cost of late tax payments can accumulate quickly. Taxpayers should carefully plan their payment schedule and consult a qualified CPA to ensure proper tax planning and avoid additional costs caused by high interest charges.

If you have any questions or need further help,

please contact us at the USCPA Luo Xia +886 980919600

or Email: ustaxproservice@gmail.com 

Also welcome to visit our website: https://www.ustaxproservice.com 

(USTAX Service LLC)