Datetime Python - Next Business Day

I would use dateutil.rrule:

import datetime
from dateutil import rrule


holidays = [
    datetime.date(2012, 5, 1,),
    datetime.date(2012, 6, 1,),
    # ...
]

# Create a rule to recur every weekday starting today
r = rrule.rrule(rrule.DAILY,
                byweekday=[rrule.MO, rrule.TU, rrule.WE, rrule.TH, rrule.FR],
                dtstart=datetime.date.today())

# Create a rruleset
rs = rrule.rruleset()

# Attach our rrule to it
rs.rrule(r)

# Add holidays as exclusion days
for exdate in holidays:
    rs.exdate(exdate)


print rs[0]

This question is common and there are different levels of solutions:

Simplest: use something like your approach of checking the weekday. One common idom is something like

d = datetime.date(2012,2,7)
next = d + datetime.timedelta(days= 7-d.weekday() if d.weekday()>3 else 1)

Once you want holidays, you can roll your own datetime "TradingDateChecker" that has to scan for the "predictable" holidays like Jan 1, July 4, Dec 25 the Friday before or Monday after those if they fall on a weekend, last Monday in May, first Monday in Sept etc.

I won't even bother posting that code here because for trading holidays, it still is insufficient.

The stock and futures markets have different holidays. If you want NYSE holidays (a common request) see below. You can't really get around keeping your own calendar since the closing dates are usually only announced for a couple of years in the future.

# For a longer list of NYSE closed dates see: http://www.chronos-st.org/NYSE_Observed_Holidays-1885-Present.html
holidays = [datetime.date(2000, 1, 17),
 datetime.date(2000, 2, 21),
 datetime.date(2000, 4, 21),
 datetime.date(2000, 5, 29),
 datetime.date(2000, 7, 4),
 datetime.date(2000, 9, 4),
 datetime.date(2000, 11, 23),
 datetime.date(2000, 12, 25),
 datetime.date(2001, 1, 1),
 datetime.date(2001, 1, 15),
 datetime.date(2001, 2, 19),
 datetime.date(2001, 5, 28),
 datetime.date(2001, 7, 4),
 datetime.date(2001, 9, 3),
 datetime.date(2001, 9, 11),
 datetime.date(2001, 9, 12),
 datetime.date(2001, 9, 13),
 datetime.date(2001, 9, 14),
 datetime.date(2001, 11, 22),
 datetime.date(2001, 12, 25),
 datetime.date(2002, 1, 1),
 datetime.date(2002, 1, 21),
 datetime.date(2002, 2, 18),
 datetime.date(2002, 3, 29),
 datetime.date(2002, 5, 27),
 datetime.date(2002, 7, 4),
 datetime.date(2002, 9, 2),
 datetime.date(2002, 11, 28),
 datetime.date(2002, 12, 25),
 datetime.date(2003, 1, 1),
 datetime.date(2003, 1, 20),
 datetime.date(2003, 2, 17),
 datetime.date(2003, 4, 18),
 datetime.date(2003, 5, 26),
 datetime.date(2003, 7, 4),
 datetime.date(2003, 9, 1),
 datetime.date(2003, 11, 27),
 datetime.date(2003, 12, 25),
 datetime.date(2004, 1, 1),
 datetime.date(2004, 1, 19),
 datetime.date(2004, 2, 16),
 datetime.date(2004, 4, 9),
 datetime.date(2004, 5, 31),
 datetime.date(2004, 6, 11),
 datetime.date(2004, 7, 5),
 datetime.date(2004, 9, 6),
 datetime.date(2004, 11, 25),
 datetime.date(2004, 12, 24),
 datetime.date(2005, 1, 17),
 datetime.date(2005, 2, 21),
 datetime.date(2005, 3, 25),
 datetime.date(2005, 5, 30),
 datetime.date(2005, 7, 4),
 datetime.date(2005, 9, 5),
 datetime.date(2005, 11, 24),
 datetime.date(2005, 12, 26),
 datetime.date(2006, 1, 2),
 datetime.date(2006, 1, 16),
 datetime.date(2006, 2, 20),
 datetime.date(2006, 4, 14),
 datetime.date(2006, 5, 29),
 datetime.date(2006, 7, 4),
 datetime.date(2006, 9, 4),
 datetime.date(2006, 11, 23),
 datetime.date(2006, 12, 25),
 datetime.date(2007, 1, 1),
 datetime.date(2007, 1, 2),
 datetime.date(2007, 1, 15),
 datetime.date(2007, 2, 19),
 datetime.date(2007, 4, 6),
 datetime.date(2007, 5, 28),
 datetime.date(2007, 7, 4),
 datetime.date(2007, 9, 3),
 datetime.date(2007, 11, 22),
 datetime.date(2007, 12, 25),
 datetime.date(2008, 1, 1),
 datetime.date(2008, 1, 21),
 datetime.date(2008, 2, 18),
 datetime.date(2008, 3, 21),
 datetime.date(2008, 5, 26),
 datetime.date(2008, 7, 4),
 datetime.date(2008, 9, 1),
 datetime.date(2008, 11, 27),
 datetime.date(2008, 12, 25),
 datetime.date(2009, 1, 1),
 datetime.date(2009, 1, 19),
 datetime.date(2009, 2, 16),
 datetime.date(2009, 4, 10),
 datetime.date(2009, 5, 25),
 datetime.date(2009, 7, 3),
 datetime.date(2009, 9, 7),
 datetime.date(2009, 11, 26),
 datetime.date(2009, 12, 25),
 datetime.date(2010, 1, 1),
 datetime.date(2010, 1, 18),
 datetime.date(2010, 2, 15),
 datetime.date(2010, 4, 2),
 datetime.date(2010, 5, 31),
 datetime.date(2010, 7, 5),
 datetime.date(2010, 9, 6),
 datetime.date(2010, 11, 25),
 datetime.date(2010, 12, 24),
 datetime.date(2011, 1, 17),
 datetime.date(2011, 2, 21),
 datetime.date(2011, 4, 22),
 datetime.date(2011, 5, 30),
 datetime.date(2011, 7, 4),
 datetime.date(2011, 9, 5),
 datetime.date(2011, 11, 24),
 datetime.date(2011, 12, 26),
 datetime.date(2012, 1, 2),
 datetime.date(2012, 1, 16),
 datetime.date(2012, 2, 20),
 datetime.date(2012, 4, 6),
 datetime.date(2012, 5, 28),
 datetime.date(2012, 7, 4),
 datetime.date(2012, 9, 3),
 datetime.date(2012, 11, 22),
 datetime.date(2012, 12, 25),
 datetime.date(2013, 1, 1),
 datetime.date(2013, 1, 21),
 datetime.date(2013, 2, 18),
 datetime.date(2013, 3, 29),
 datetime.date(2013, 5, 27),
 datetime.date(2013, 7, 4),
 datetime.date(2013, 9, 2),
 datetime.date(2013, 11, 28),
 datetime.date(2013, 12, 25)]