A Non tourist visa is given for 1 year whereas a tourist visa is given for 150 days.

The Immigration Department charges about $25 to $100 for an extension. It takes couple of hours. Documents needed are US Passport, Relationship verification certificate and Birth certificate.

See Section 1.i at http://www.immi.gov.np/nontouristvisa.php
and
http://www.immi.gov.np/apendix.php
O. Visa Fees:

1. The
   visa fees or other fees to be charged for the issuance of a visa for
   the entry into or presence in Nepal, for the extension of the visa or
   the regulation of the visa of the foreigner who has over-stayed or the
   issuance of the travel permit or the transference of the visa shall be
   prescribed in Appendix -9.
   Provided, however, that the children below the age of ten years shall be exempted from visa fees.

1. While regularizing the
   visas of those foreigners who have stayed without getting the validity
   of business, study and non-tourist visas extended:
   In
   the case of those who have stayed without getting the validity of
   business, study and non-tourist visas extended, an additional fee at
   the rate of 50% of the fees chargeable pursuant to these Rules for the
   visas on which they have stayed for the period not exceeding 30 days
   and at the rate of 100% for the period thereafter shall be charged.

General Information
:

Location, contact No. and Working Hours


Location :    The Department of Immigration is located at Maitighar, Kathmandu.


Tel :            977-1-4223590 / 4222453 / 4223681/ 4221996 / 4224757

Fax :           977-1-4223127

Emails
:        mail@immi.gov.np

Web :          http://www.immi.gov.np



Office Hours



Sunday to Thursday: 10 a.m. - 17 p.m. in summer

        
       
             
10 a.m. - 16 p.m. in winter (Nov. to Jan.)


Friday:                     10 a.m. -15 p.m.


Application Hours

Sunday to Thursday: 10 a.m. - 15 p.m.




Friday:                     10 a.m. -15 p.m.

Good Luck.