Supplement, dated October 10, 2005,
                      to the Prospectus, dated May 2, 2005,
                       of Seligman Common Stock Portfolio,
                      a series of Seligman Portfolios, Inc.

Effective October 10, 2005, the following information supersedes and replaces
the fourth, fifth, sixth and seventh paragraphs under the caption "Principal
Investment Strategies" on page 8 of the Prospectus:

Securities are chosen using an investment strategy, consisting of: analytical
security evaluation; fundamental analysis; and portfolio construction. The final
portfolio composition, therefore, is a reflection of these analytical and
qualitative techniques.

Security Evaluation. The investment manager applies analytical techniques to
evaluate a broad universe of stocks based on a number of factors. The factors
may include projected earnings, earnings surprise forecasts, projected cash
flow, price momentum, historical income and balance sheet items, and other
factors.

Fundamental Analysis. In addition to evaluating analytical measures, the
investment manager applies traditional fundamental research to gather
qualitative information. This means the investment manager concentrates on
individual company fundamentals, focusing on companies that the investment
manager believes are well managed and possess the opportunity for earnings
growth.

Portfolio Construction. During the course of the security evaluation and
fundamental analysis discussed above, the investment manager assigns weightings
to the stocks being considered for investment. The investment manager considers
the risk and expected return of each individual stock as well as the overall
portfolio. The manager also evaluates exposure by sector, industry, market
capitalization and other categories.

The Fund generally sells a security if the investment manager believes its
target price has been reached, its fundamentals have deteriorated, or ongoing
evaluation reveals that there are more attractive investment opportunities
available.