UPDATE 1-Australia's Spotless to bid $510 mln for Programmed

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SYDNEY, March 27 (Reuters) - Australian industrial services company Spotless Group Ltd SPT.AX said it plans to make a cash and stock takeover offer for Programmed Maintenance Services Ltd PRG.AX, valuing Programmed at A$556 million ($510 million).

Spotless' offer values Programmed shares at A$6.11 per share, a 34.6 percent premium to Programmed's closing price on Wednesday. Spotless said it has a 13.2 percent relevant interest in Programmed.

If the deal goes through, Spotless said the combined group would have a proforma market capitalisation of about A$1.25 billion, and it expects to make pre-tax cost savings of about A$18 million per annum in the second full-year of the ownership.

The merged group would have in excess of 40,000 employees.

Under the offer, Programmed shareholders will have the option of receiving a maximum of A$3.00 in cash plus 0.825 Spotless shares for every Programmed share held.

Spotless said Goldman Sachs JBWere would provide debt facilities for the offer. Spotless could also undertake a equity raising as part of the offer.

The offer is subject to 90 percent acceptance.

Programmed provides property maintenance services, including painting, while Spotless offers food services, cleaning and laundry services.

Spotless said its offer was at a price-to-earnings ratio of 17.9 times Programmed's forecast March earnings. It said the offer has the support of some of Programmed's largest shareholders. ($1=A$1.09) (Reporting by Denny Thomas; editing by James Thornhill)