* Yellen's two-day testimony before Congress to start at 10 a.m.
* Home Depot climbs in premarket after earnings, buyback
* Toll Brothers rises in premarket after results
* Futures: Dow up 21 pts, S&P off 0.25 pt, Nasdaq off 3 pts (Adds quote, updates prices)
By Chuck Mikolajczak
NEW YORK, Feb 24 (Reuters) - U.S. stocks were poised for a flat open on Tuesday, as the Dow and S&P 500 hold near record levels ahead of testimony by Federal Reserve Chair Janet Yellen and a flurry of economic data.
Yellen will give the central bank's semi-annual Monetary Policy Report to the Senate Banking Committee at 10 a.m. (1500 GMT), the first of her two days of testimony. Investors will attempt to parse her commentary for clues on the timing of an interest rate hike in the wake of the dovish Fed minutes released last week.
"It's a classic wait-and-see day," said Art Hogan, chief market strategist at Wunderlich Securities in New York.
"She's got a very difficult job of trying to talk Wall Street into the fact the January minutes weren't nearly as dovish as the Street interpreted them, and a June liftoff is still a credible possibility because we are data-dependent."
The latest indicator on the health of the housing market is due at 9 a.m. (1400 GMT) with the S&P/Case Shiller home price index for December. Expectations call for a year-over-year increase of 4.3 percent, matching November's increase, the slowest since October 2012.
Home Depot shares gained 3.3 percent to $115.99 after the home improvement retailer reported a better-than-expected rise in quarterly same-store sales and said it would buy back $18 billion of its shares.
S&P 500 e-mini futures were down 0.25 point and fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract, indicated a flat open. Dow Jones industrial average e-mini futures rose 21 points and Nasdaq 100 e-mini futures lost 3 points.
On Monday the Nasdaq climbed for a ninth straight session, its longest winning streak since September 2010, to within striking distance of the 5,000 mark, a level it has not reached since March 2000. The Dow and S&P 500 edged lower as energy shares weighed.
Other data expected on Tuesday includes the flash Markit services PMI at 9:45 a.m. (1445 GMT). February consumer confidence along with readings on the services sectors from the Richmond and Dallas Fed are due at 10 a.m. (1500 GMT).
JPMorgan Chase climbed 2.8 percent to $60.99 after the bank's outlook in an investor presentation, including an increase of about 10 percent in core loan growth in 2015.
Comcast Corp, the largest U.S. cable operator, posted fourth-quarter revenue that marginally beat estimates and boosted its buyback program to $10 billion. Its shares slipped 0.4 percent to $58 in premarket.
Macy's slipped 1.2 percent to $63.40 in premarket after the department store chain reported a less-than 2 percent rise in sales in the holiday shopping quarter, falling short of analysts' estimates.
Toll Brothers climbed 4.5 percent to 38.75 before the opening bell. The largest U.S. luxury homebuilder, reported a higher-than-expected quarterly profit and raised the low end of its full-year home delivery forecast.
Reporting by Chuck Mikolajczak; Editing by Chizu Nomiyama and Nick Zieminski