Here's what you need to know before the US open at 2:30pm.
The US pre-market is climbing ahead of the open, betting the Fed will not move to hike interest rates when it announces its decision at 7pm today. The S&P is up by 0.43 per cent, while the Nasdaq is 0.53 per cent higher. The Dow is up 0.43 per cent.
European and Asian markets are also both feeling positive ahead of the Fed. The Nikkei in Japan climbed by 1.9 per cent as the yen dropped.
The Fed's rate committee is meeting to decide whether to raise interest rates for only the second time since the financial crisis. The decision is out at 7pm tonight, London time.
This week is realistically the Fed's last chance to change rates before the US election.
While the rate-setting Federal Open Market Committee (FOMC) will meet just one week before the 8 November vote, the FOMC is unlikely to move so close to the big date.
Despite rate-setters, including chair Janet Yellen, insisting the Fed could still move, markets aren't buying it.
Futures prices on overnight interest rate swaps - a guess on what the Fed's rate will be on any given day - indicate just a 20 per cent chance of a rate rise. Earlier this year the chances of a hike at - or before - the September FOMC meeting touched 90 per cent.
Not everyone agrees however, investment banking teams at both Barclays and BNP Paribas are going against the grain and predicting the Fed will act.
Giving drug prices a shot in the arm...
The chief executive of US pharma firm Mylan, Heather Bresch, is facing the US Congress today to answer questions over the recent price hikes on the life saving allergy treatment, Epipen.
The cost of a standard two-pack of Epipens has risen to around $600 from $100 in 2009. Mylan acquired the rights to the drug in 2007.
Mylan said last month it would make a cheaper, generic version of Epipen available after the firestorm erupted around the price.
Mylan's share price has fallen by almost 20 per cent since US presidential hopeful Hillary Clinton and a senator whose daughter uses the product piled pressure on the company.
Stocks to watch
Courier giant FedEx has beaten expectations for its latest quarter, it revealed last night. The firm earned $2.90 a share on revenue of $14.7bn.
Tech behemoth Microsoft has announced a huge share-buyback program, with plans to purchase $40bn worth of stock, or nearly 10 per cent of outstanding shares.
It also said it would hike its quarterly divided by $0.03 a share to $0.39.
And US lender Wells Fargo is again in the spotlight after facing the Senate's banking committee yesterday. Legendary investor Warren Buffett is rumoured to planning on berating the bank's chief executive, John Stumpf, over the fake account scandal.
Buffett's Berkshire Hathaway is Wells Fargo's largest investor, holding a 9.5 per cent stake.
Companies reporting today
Food giant General Mills has already posted results today, with revenue of $3.9bn, down from $4.2bn, in its first quarter. Net income came in at net income of $409m, slightly ahead of expectations for the Häagen-Dazs owner.
Numbers are also out this morning form CarMax, the largest used-car retailer in the US.
We'll hear from Bed Bath & Beyond after markets close.
In economic news
Before the Fed announcement, the latest crude oil inventories are out at 3:30pm. The oil price has rallied today after a surprise fall in inventories from the American Petroleum Institute. The data showed a draw of 7.5m barrels versus expectations for a build of 3.4m barrels.