中美 1984 年签订了避免双重征税的协议，以下两条是留学生和访问学者享受税务减免的政策依据，适用于在美国的中国居民，也适用于在中国的美国居民。 RA（Resident Alien）和 NRA（Nonresident Alien）的定义和区别参见下文。
教师、教授和高校研究人员 3 年内豁免联邦税
官方文件
ARTICLE 19
(Teachers, Professors and Researchers)
An individual who is, or immediately before visiting a Contracting State was, a resident of the other Contracting State and is temporarily present in the first-mentioned Contracting State for the primary purpose of teaching, giving lectures or conducting research at a university, college, school or other accredited educational institution or scientific research institution in the first mentioned Contracting State shall be exempt from tax in the first mentioned Contracting State for a period not exceeding three years in the aggregate in respect of remuneration for such teaching, lectures or research.
中国居民来美国的高校和科研机构从事教学、演讲、做研究，3 年内的这部分收入无需缴纳联邦税；参见《中美税务协议全文（中英文）》 。访问学者一般是 J-1 身份，也有少数的 H-1B，如上面这位读者。延伸阅读：《在美国读博士和博士后报税的经验》 。
“Three years in the aggregate” 如何计算
既然是「aggregate」，所以无需是连续的 3 年，若中途离开美国、回到中国、之后再次回来美国，仍然可以接着计算。参见 IRS 在这份文件里举的例子：Thus, for example, a resident of China who visits the United States to conduct research at the National Institute of Health (NIH) for two years, 1986 and 1987, returns to China for a year, and then comes back for another year of research at NIH in 1989 would be exempt from tax on his NIH remuneration for each of the three years. However, if he stayed at NIH in 1990 or returned at a later time the exemption would no longer be available 。
「年」的计算是从抵达美国之日起计算 365 天。最接近官方解释的是 IRS 2014 年的一份备忘录，里面引用了 US-UK Tax Treaty 的先例，并举了一个例子，是这样计算的：
It is the purpose of[the exemption under Article 18 of the 1945 U.K. treaty] that such exemption shall cease at the end of 2 years from the date of[the individual’s] initial arrival in the United States. Thus, if[the individual] reaches the United States on July 1, 1945, he is exempt with respect to his remuneration earned in the United States up to June 30, 1947.
在这个例子里，美、英有类似的免税条款，但是只适用于 2 年（而不是 3 年），假设此人 1945 年 7 月 1 日抵达美国开始教学，他的免税期到 1947 年 6 月 30 日为止。中美条约我没找到如此翔实的例子，从我目前看到的信息来判断，应该也是按照这种计算方式。
留学完成之后立刻留下来教书也可以算
上面提到的 2014 年备忘录，是关于中美 Treaty Article 19 是否适用于在美国留学之后、留下来教学的人员，其意见认为，只要满足以下 4 个条件即可使用 Article 19，不需要离开美国：
ISSUE
Whether an individual who is present in the United States solely for the purpose of education, training, or obtaining special technical experience and who receives benefits under Article 20 (Students and Trainees) of the U.S.-China Income Tax Treaty (the “Treaty” or the “Chinese treaty”) may, without leaving the United States (or without leaving the United States for a period of more than one year), begin employment as a teacher, lecturer, or researcher in the United States and receive benefits under Article 19 (Teachers, Professors and Researchers) of the Treaty.
CONCLUSION
Yes, the individual may receive benefits under Article 19 of the Treaty provided
- the individual is a resident of China for the year at issue or was a resident of China immediately before visiting the United States as a student or trainee;
- the individual is “temporarily present” (notwithstanding the fact that the individual was present in the United States in prior years solely for educational or training purposes) in the United States for the year at issue for the primary purpose of teaching, giving lectures, or conducting research;
- the individual’s teaching, lecturing, or research activities take place at a university, college, school, or other accredited educational institution or scientific research institution in the United States; and
- the individual has not claimed benefits under Article 19 for more than three years in the aggregate.
只要满足上述条件，即使是留学毕业之后立刻留在美国教书（期间没有离开美国），仍然可以使用 Article 19 免税。若以前已经用完了 Article 19 的 36 个月免税条款，今后就不能再用了；比如说：你 2000/07/01-2003/06/30 用 Article 19 享受了 3 年的免税期，回中国工作了几年，2006 年再次来美国从事科研教学工作，就不能再享受 3 年的免税了。
留学生和培训生有 5,000 美元免税额度
ARTICLE 20
(Students and Trainees)
A student, business apprentice or trainee who is, or was immediately before visiting a Contracting State, a resident of the other Contracting State and who is present in the first- mentioned Contracting State solely for the purpose of his education, training or obtaining special technical experience shall be exempt from tax in that Contracting State with respect to:
- payments received from abroad for the purpose of his maintenance, education, study, research or training;
- grants or awards from a government, scientific, educational or other tax-exempt organization; and
- income from personal services performed in that Contracting State in an amount not in excess of 5,000 United States dollars or its equivalent in Chinese yuan for any taxable year.
The benefits provided under this Article shall extend only for such period of time as is reasonably necessary to complete the education or training.
中国居民来美国学习或接受培训，学费、奖学金等收入无需交税；其他个人收入享有 5,000 美元的免税额度。这里的 taxable year 是指 calendar year，而不是 365 天。留学生一般是 F-1 或 M-1 签证。
更多 # 2023 报税 # 文章
转换身份可能无法享受豁免
本站一位作者以 F-2 身份入境美国，后来转成 F-1 读书，用学校提供的软件报税时发现无法 claim 这一条 treaty 。根据读者 Andy F 的查找，IRS 在 2002 年对此的解释如下：
Individuals who first enter the U.S. as an F-2 or H-4 are NOT eligible to claim the tax treaty benefit for students as they did not enter the U.S. for the purpose of being a student. The Treasury Dept is very specific about China in particular.
In general, persons who change immigration status from dependent to principal are not eligible for tax treaty benefits UNLESS the change to principal occurs within two months from the original arrival in the U.S. The IRS maintains that it is the PURPOSE for original arrival in the U.S. that determines treaty eligibility. Therefore, if someone changes purposes (goes from dependent to student, for example) they cannot benefit from tax treaty exemptions. AND, in the case of an F-2 who has been in the U.S. for a year or so, passes the TOEFL and goes home for the summer to apply for an F-1 visa and returns that fall, the IRS still says a resounding no to treaty benefits. This is because the NRA hasn’t been physically residing in the treaty country for at least a year prior to their arrival as a student in the U.S. Officially, they’re from “no country” for tax purposes, because they’re an NRA in the U.S., but U.S. tax law also has them as a nonresident in the home country. (There are a few exceptions to this, but mostly for diplomats who are considered tax residents of their home country no matter where they live or how long they’ve been away from home.)
IRS 认为，他们使用其他签证入境，其目的不是来求学，因此不能享受此 treaty 。
协议仅适用于对方的税务居民
有读者问：「第一次来美国 B2 签，待了 20 天左右。第二次 J2 签，找到职位后回国办理 J1（第二次在美国时间不超过 2 个月）。第三次以 J1 签入职，可是学校软件显示不可豁免，学校负责人说是需要在国内待满一年才能豁免。是真的不能豁免吗？」
这是因为，该协议仅适用于对方国家的（税务）居民。如果你来美国之前不是中国的（税务）居民，那么你将不能使用该税务协议的豁免。怎么样才算中国的税务居民呢？如果你在美国停留之后回中国，需要在中国待满至少一年。若未待满一年、又来美国，IRS 认为你来美国之前不是中国的税务居民。仍然是参见上面的引文。
This is because the NRA hasn’t been physically residing in the treaty country for at least a year prior to their arrival as a student in the U.S. Officially, they’re from “no country” for tax purposes, because they’re an NRA in the U.S., but U.S. tax law also has them as a nonresident in the home country.
#