UPDATE 1-FACTBOX-US health overhaul to hit corporate profits

(Adds detail of AT&T, 3M charges)

March 26 (Reuters) - The U.S. healthcare overhaul, signed into law this week by President Barack Obama, will cost U.S. companies millions this year.

Companies such as Deere & Co (DE.N) and Caterpillar Inc (CAT.N), which have large ranks of retirees, can no longer deduct from their taxes the subsidies paid by the federal government for retiree drug benefits. [ID:nN25229640]

Large U.S. employers have started detailing the expected hit to their bottom line as a result of changes to the $2.5 trillion U.S. healthcare system. The tally so far:

* AT&T Inc (T.N) said on Friday that it would record a $1 billion noncash charge for the current quarter, and said it will be evaluating prospective changes to the healthcare benefits it offers to both active and retired workers, according to a filing with the U.S. Securities and Exchange Commission.

* In its regulatory filing, Caterpillar described the move as a tax hike. Accounting standards require the world's largest maker of earth-moving equipment to book a $100 million after-tax charge to reflect the change during the current fiscal quarter.

* Deere, a maker of farm equipment, said it expects to record a $150 million charge, mostly in its current fiscal second quarter. The expense was not included in the company's earlier 2010 forecast, which called for net income of about $1.3 billion.

* 3M will record a one-time noncash charge of up to $90 million or 12 cents per share. It said its January forecast of 2010 earnings did not include the impact of the healthcare law.

* Diversified U.S. manufacturer Honeywell International Inc (HON.N) in January estimated that healthcare reform would trim its first-quarter earnings by 4 to 5 cents per share. A Honeywell spokesman said on Thursday that the company had not updated the earlier cost estimate and would continue to review the legislation.

* AK Steel Holding Corp (AKS.N) will record a noncash charge of approximately $31 million in the first quarter, due to a reduction in the value of the company's deferred tax asset as a result of a change to the tax treatment of Medicare Part D reimbursements.

* Valero Energy Corp (VLO.N) said it expects to take a charge to earnings of between $15 million and $20 million in the first quarter due to the new healthcare legislation, and said it expected further tax costs to be calculated later.