加拿大税局Canada Revenue Agency (CRA)颁布的新法令中，从2021年7月1日开始，规定以下情况中，非居民卖家需要申请销售税号Goods and Services Tax / Harmonized Sales Tax（GST / HST），我直接把税局原文中的定义复制黏贴给大家，一些符合跨境电商的情况我就简单翻译一下。
流媒体卖家
A non-resident vendor or a non-resident distribution platform operator vendor who sells taxable digital products or services, such as online music streaming or traditional services, to Canadian consumers and Canadian entities who are not registered under the normal GST/HST?
A distribution platform operator who facilitates through your platform the supplies of taxable digital products or services, such as online music streaming or traditional services, to Canadian consumers and Canadian entities who are not registered under the normal GST/HST?
卖家在亚马逊等第三方平台销售或者第三方平台本身
A non-resident vendor or a non-resident distribution platform operator vendor who makes the supply of qualifying goods (also known as “qualifying tangible personal property supply”) including goods that are delivered or made available in Canada, such as goods located in a fulfillment warehouse or goods shipped to a purchaser in Canada?
自有平台卖家（独立站等）
A distribution platform operator who facilitates the supply of qualifying goods (also known as “qualifying tangible personal property supply”) through your platform including goods that are delivered or made available in Canada, such as goods located in a fulfillment warehouse or goods shipped to a purchaser in Canada?
短租或短租网站卖家
A supplier of taxable supplies of short-term accommodation in Canada or an accommodation platform operator that facilitates such supplies through your platform?
当你是上述卖家时，而你的销售额大于3万加币，你就必须登记GST号。
如果你刚注册公司或者税号，预计销售额会超过3万加币一年，最好也先登记GST号。
对于加拿大公司来说，公司注册后一般都会申请Business Number（BN），有了这个BN号码之后，才可以申请各种税号。这些税号包括进出口关税号RM号，销售税号RT号，所得税RC号，薪酬税RP号，信息申报RZ号。如果你不清楚你要申请哪种税号，一定要咨询会计师或者财税顾问，这些税号一旦申请了，除了RM号，其他税种就算你没有产生税款，都是要按照一定周期申报的。
如果你在亚马逊、沃尔玛等第三方平台或者自由平台销售的公司不是一个加拿大公司，是一个中国或者外国公司或个人，你也可以申请BN号码和GST号等税号。
现阶段对于跨境电商来说，如果你没有雇佣任何人在加拿大，没有在加拿大有实体地址，没有实体经营，只是单纯的使用加拿大的仓库，或者直接发货给加拿大的买家，你需要的只是BN号和GST号去清关以及代收代付销售税。
申请BN号和GST号，只需要以下文件：
营业执照（主体公司）
法人及股东身份证明
填写一些公司及个人信息
通信地址和联系方式（最好是加拿大的通信地址）
