<PAGE>
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+A registration statement for Pacific Select Fund relating to shares of the +
+Focused 30 and Strategic Value Portfolios has been filed with the Securities +
+and Exchange Commission, but has not yet become effective. The information in +
+the Prospectus is not complete and may be changed. Interests in the new +
+Investment Options and shares of the Focused 30 and Strategic Value +
+Portfolios may not be sold until the Fund's registration statement is +
+effective. This supplement and Preliminary Prospectus are not an offer to +
+sell interests in the Investment Options or shares of the Focused 30 and +
+Strategic Value Portfolios and do not solicit an offer to buy interests or +
+shares in any state where the offer or sale is not permitted. +
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Supplement to Prospectus Dated May 1, 2000 for
Pacific One, a variable annuity contract
issued by Pacific Life Insurance Company
Date of Supplement: August 7, 2000
This supplement changes the Prospectus to reflect the following:
---------------------------------------------------------
Two new Variable The new Investment Options will invest in two new
Investment Options Portfolios of the Pacific Select Fund called the
will be available Focused 30 and Strategic Value Portfolios. Below is
October 2, 2000 information summarizing the new Portfolios.
. Focused 30 Pacific Life Insurance Company, the adviser, and the
. Strategic Value Fund have retained Janus Capital Corporation as
Portfolio manager.
<TABLE>
<CAPTION>
-------------------------------------------------------------------------
Primary Investments
Portfolio Objective (under normal circumstances)
-------------------------------------------------------------------------
<S> <C> <C>
Focused 30 Long-term growth of capital. Common stocks selected
for their growth
potential.
Strategic Value Long-term growth of capital. Common stocks with the
potential for long-term
growth of capital.
-------------------------------------------------------------------------
</TABLE>
This chart is only a summary. For more complete
information on the Portfolios, including a discussion
of each Portfolio's investment techniques and the risks
associated with its investments, see the accompanying
Fund Preliminary Prospectus. You should read the
Prospectus carefully.
---------------------------------------------------------
An Overview of The following is added to the chart under Fees and
Pacific One Expenses Paid by the Pacific Select Fund:
is amended
<TABLE>
<CAPTION>
-------------------------------------------------------------
Portfolio Advisory fee Other expenses Total expenses
-------------------------------------------------------------
As an annual % of average daily net assets
<S> <C> <C> <C>
Focused 30* 0.95 0.08 1.03
Strategic Value* 0.95 0.08 1.03
</TABLE>
* Other expenses are estimated. There were no actual
advisory fees or other expenses for these Portfolios
in 1999 because the Portfolios will start on October
2, 2000. See page 7 of the Preliminary Prospectus for
information about expense caps through December 31,
2001 for these Portfolios.
<PAGE>
---------------------------------------------------------
The following is added to Examples:
The following table shows the expenses you would pay on
each $1,000 you invested if, at the end of each period,
you: annuitized your Contract, surrendered your
Contract and withdrew the Contract Value, or did not
annuitize or surrender, but left the money in your
Contract.
These examples assume the following:
. the Contract Value starts at $80,000
. the Investment Options have an annual return of 5%
. the Annual Fee is deducted even when the Contract
Value goes over $100,000 and a waiver would normally
apply.
without rider reflects the expenses you would pay if
you did not buy the optional Enhanced Guaranteed
Minimum Death Benefit Rider.
with rider reflects the expenses you would pay if you
bought the optional Enhanced Guaranteed Minimum Death
Benefit Rider. These expenses depend on the age of the
youngest Annuitant on the Contract Date.
These examples do not show past or future expenses.
Your actual expenses in any year may be more or less
than those shown here.
<TABLE>
<CAPTION>
---------------------------------------------------------
Expenses($)
---------------------------------------------------------
Variable Account 1 yr 3 yr 5 yr 10 yr
---------------------------------------------------------
<S> <C> <C> <C> <C>
Focused 30
without rider 25 77 132 281
with rider: age 0-65 26 80 137 291
with rider: age 66-75 28 86 147 310
---------------------------------------------------------
Strategic Value
without rider 25 77 132 281
with rider: age 0-65 26 80 137 291
with rider: age 66-75 28 86 147 310
---------------------------------------------------------
</TABLE>
---------------------------------------------------------
Choosing Your This information is added to the discussion in the
Investment Options Prospectus on Choosing your Investment Options.
is amended
You may instruct us to allocate all or part of your
Purchase Payments to the Focused 30 and Strategic Value
Investment Options on or after October 2, 2000. You may
not allocate your Purchase Payments to these Investment
Options prior to October 2, 2000, when the Options
first become available.
---------------------------------------------------------
Transfers is This information is added to the discussion in the
amended Prospectus on Transfers.
You may instruct us to transfer Accumulated Value to a
Variable Investment Option and specify a future date on
which the Accumulated Value is to be transferred. This
instruction may cover any Variable Investment Option
currently available under your contract and the Focused
30 and Strategic Value Investment Options. For the
Focused 30 and Strategic Value Investment Options, you
may not specify a date prior to October 2, 2000, when
the Options first become available. If you specify
October 2, 2000 for the Focused 30 and Strategic Value
Investment Option, and we receive the instructions
prior to that date, the requested amount will be
transferred effective as of the close of business on
October 2, 2000. You may revoke your transfer
instructions at any time before we transfer Accumulated
Value by
2
<PAGE>
providing us with a revocation in proper form, which we
must receive not later than 4:00 p.m. Eastern time on
the last Business Day before the date you have
specified for a transfer. While highly remote, there is
a possibility that the Focused 30 and Strategic Value
Investment Options will not become effective on October
2, 2000, in which case we would not effect the transfer
to these Options, and your Accumulated Value would
remain in the Investment Option from which you
requested it be transferred until the day the Focused
30 and Strategic Value Portfolios become effective, if
ever, unless you instruct us otherwise.
---------------------------------------------------------
Choosing Your This information is added to the discussion in the
Annuity Option Prospectus on Choosing Your Annuity Option.
is amended
If you annuitize and select the variable annuity
payment option, the Focused 30 and Strategic Value
Variable Investment Options will be available effective
October 2, 2000, unless the Focused 30 and Strategic
Value Portfolios do not become effective on that date.
3
