What is the SSS membership type for a Filipina, formerly an employed SSS member, who has married a Japanese and has settled in Japan as a full-time housewife?

If she wants to continue as an SSS member, what would be her member classification?

She can choose one of these:

1.  Voluntary
2.   Overseas Filipino Worker (OFW)

What are the advantages of one membership type over the other?

There are only 2 advantages of the OFW classification over Voluntary:

1. SSS Payment Deadline

Mas flexible ang payment deadlines ng mga OFWs.
OFWs can pay their contributions or loans for any month of the year at any month during the current year.

Halimbawa, December na, puede pa ring bayaran ang for January, or for first quarter, or for 2nd quarter, or for 3rd quarter.

2. SSS Flexi-Fund

SSS can save or invest in SSS Flexi-Fund. Ano ba itong Flexi-Fund?  There are tips about SSS Flexi-Fund here.

Meron bang difference sa minimum contribution amount?

Yes. The minimum contribution for OFWs is 520 pesos a month.
Voluntary members can choose from 104 pesos a month to 1,560 pesos a month, depending on their monthly earnings.

Meron bang pagkakaiba sa benefits between OFW and Voluntary members?

Wala. Pareho ang pag-compute ng pensions or benefits, ke Voluntary ka or OFW ka. Depende pa rin sa amount of monthly contributions and number of years you have contributed to SSS.

Sources:  SSS Newsletter, December 2012
               SSS Circular No. 32-P, signed Nov 15, 2006
               SSS Circular No. 2012-014, signed June 27, 2012

Table of monthly SSS contributions
SSS payment deadlines
SSS payment of contributions via the Internet -- bancnetonline.com