The Single Status Certificate (also known as: Affidavit of Single Status, Certificate of No Record of Marriage, Certificate of No Impediment, Single Status Statutory Declaration, Certificate of Legal Capacity to Contract Marriage,  etc).  This is intended to show that you are not currently married. Each country has its own way of providing this, and some countries offer the service via an embassy or consulate in China, so you should check your own country' s websites to find the relevant procedures.

In some countries it is possible for persons to obtain a certificate form stating they are eligible to marry, Australians can obtain a 'No Record of Marriage (Single Status) Certificate.  However, many countries cannot provide this so you must make a formal statement, often known legally as an 'affidavit', that you are single. This is the way in the USA, please read more information about the "Marriage Registration in China for US Citizens" at http://www.chinaconsulatesf.org/eng/lszj/rz/t42743.htm. If you cannot obtain a standard form, you should draft your own affidavit, if possible using the preferred style of your country, stating your full name and address, occupation and employer, and your passport number.  State that you have never been married before, or that you have not remarried since your divorce or became widowed on whatever date. You can get this document as well at the Canadian Embassy in Beijing. It actually takes 15 minutes. The Embassy office for this document was only open specific days (Tues & Thurs). It cost $50 CAD or about 310 RMB in 2009.

Typically, the next step is to have the affidavit notarized according to the law of the local jurisdiction.  This includes signing the document and having it witnessed by a notary public or an equivalent in your legal system.  However, in some jurisdictions there can be extra steps.  In the USA you must send the notarized affidavit to the Secretary of the State Office of the state in which it was executed although in some states you must first send it to the notary public's county clerk.

In Australia, in cases where a person cannot obtain a  Single Status Certificate they can obtain a form called a Certificate of No Impediment to Marriage from the Department of Foreign Affairs and Trade – in essence it is a structured affidavit or 'statutory declaration'.

Even just considering two countries we can see there are many variations on the basic idea.  In Canada and Britain the requirements are similar to what has been described here. Clearly, you will have to check exactly what the requirements are for where you live.  Remember that in many countries a certificate of single status is not part of its system, so you use the general purpose affidavit or swearing on oath.  If you are not truthful, you are breaking the law where you made the affidavit, and you will probably break the heart of your loved one when you are found guilty of bigamy!

You must complete the Application for Authentication of Notarization form at the local Chinese Consulate and submit it to them for authentication. You must submit it with the legal document from overseas (typically, the notarized affidavit) and pay the fee.  The handling time is normally four working days but for an extra fee it can be processed quicker.

You need to contact your consulate or embassy in China to find more information about how to get No Record of Marriage to use in China.