He was born on May 12, 1881 on a farm in Whitehall, Washington County, New York, the son of George Neddo (1836–1916) and Delia (Archambault) Neddo (1850–1913). Then he worked with his father in the family"s century-old boat-building business.
He attended the public schools, and graduated from Albany Business College.
At the same time he was an adjuster for several marine insurance companies. In 1908, he sold the boat business and opened a general store instead. Later he also engaged in banking, and was President of the Merchants National Bank of Whitehall.
He held many local offices, being at times a canal superintendent, town clerk, postmaster, and president of the school board.
In January 1947, his 38-year-old son Francis J. Neddo, a lawyer in Saratoga Springs, was killed in a car accident. Neddo was an alternate delegate to the 1948 Republican National Convention.
He resigned his seat in 1949, to run for the State Senate seat vacated by the appointment of Benjamin F. Feinberg as Chairman of the New York State Public Service Commission. He died on January 11, 1957, at his home in Whitehall, New New York
And was buried at the Neddo Cemetery there.
He entered politics as a Republican, and was a delegate to the 1898 Republican state convention, and much later a member of the Republican State Executive Committee. Neddo was a member of the New York State Assembly (Washington Company) from 1941 to 1949, sitting in the 163rd, 164th, 165th, 166th and 167th New York State Legislatures. Neddo was a member of the New York State Senate from 1950 until his death in 1957, sitting in the 167th, 168th, 169th, 170th and 171st New York State Legislatures.
