The Senate Finance Committee and the House Ways and Means Committee approved separate plans last week that propose a wide range of tax changes. The Senate and House are expected to consider the bills within the next two weeks, and differences must be resolved by a conference committee.

The House and Senate bills would:

Extend the 3 percent tax on telephone use rather than allowing it to expire this year. Freeze the top rate for the estate and gift tax at 55 percent, rather than allowing it to fall to 50 percent as scheduled. Repeal the accounting method that allows defense and construction contractors to delay payment of some taxes. Grant relief to taxpayers who pay on an estimated basis this year, allowing them to pay 80 percent of their ultimate bill without penalty rather than 90 percent as set by the 1986 law. Impose new user fees for various services of the Internal Revenue Service, Customs Service and Bureau of Alcohol, Tobacco and Firearms, such as IRS rulings requested by one individual or company. Allow the IRS to continue withholding taxpayers' refunds to pay overdue debts to federal agencies.

The House bill would: Limit interest deductions on home mortgages to loans of $1 million or less. Limit interest deductions on home equity loans to loans of $100,000 for all taxpayers. This would not be included in the $1 million limit. Disallow interest deductions on loans used to buy boats or mobile homes claimed as a second home. Deny deductions for interest of more than $5 million per year if the debt is used to acquire 50 percent or more of another company's stock. Require "corporate raiders" to pay a 50 percent excise tax on gains on stock later sold back to the company if the attempted takeover fails.

The Senate bill would: Levy the 1.45 percent Medicare payroll tax on all salary income starting in 1988, rather than applying it only to the first $45,000. Repeal the windfall-profits tax on oil companies. Adopt a set of "taxpayer-rights" provisions giving taxpayers more legal tools against the IRS.