Rough Savage 1895, 1899 and 99 serial number dating, based on the data I have collected over the years.

1895's:

Serial number 3000-5000 manufactured in 1896.
Serial number 5000-9999 manufactured in 1897.
These are rough numbers based on letters from the historian, there are a few guns mixed into the higher numbers with a 1898 manufacture date but few and far between.

1899's:

1899's and 99's up to serial number 566000 can be dated using the dating tool at savage99.com.
http://www.savage99.com/savage99_dates.htm

Savage 99's:

During WW2 there were a small amount of 400,000 serial numbered 99's made, though not alot of info is known on these I do have a few numbers to work off of.

416XXX made in 1941
4206XX made in early 1943
422XXX mid 1943
427XXX Mar 1945
429XXX mid 1945

The 500,000 serial number started in May of 1947.

500,000-510,000 made in late 1947 or early 1948.
510,000-520,000 made in 1948
520,000-535,000 made in 1949
535,000-595,000 made in 1950 although there are overlapping numbers in the late 580XXX-594XXX and you may find a 1951 date code on your 99. A date code is a small oval with an inspectors number and year of manufacture stamped inside of it. It is very small and sometimes lightly struck so you may need a magnifying glass to find it. Usually found on the lever boss of Savage 99's. The letter will start at A for 1949 and X for 1970, the O and Q were not used so as to not get them mixed up.
595,000-620,000 made in 1951
620,000-652,000 made in 1952
652,000-720,000 made in 1953
720,000-756,000 made in 1954
756,000-775,000 made in 1955
775,000-800,000 made in 1956
800,000-900,000 are very uncommon, only 502 99's were made inbetween this serial range most of them starting with 835,XXX as the first three numbers.
900,000-925,000 made in 1956
925,000-952,000 made in 1957
952,000-960,000 made in 1958
960,000-968,000 made in 1959

968,000 stopped the 900's and the move to Westfield Mass started the 1,000,000 serial range.

1,000,000-1,010,000 made in 1960
1,010,000-1,039,000 made in 1961
1,039,000-1,053,000 made in 1962
1,053,000-1,065,000 made in 1963
1,065,000-1,084,000 made in 1964
1,084,000-1,110,200 made in 1965
1,110,200-1,130,000 made in 1966
1,130,000-1,160,000 made in 1967
1,160,000-1,182,000 made in 1968

1969 started the A series serial range, please return to top of the page to Mr, Furious's table.

AH Fox serial numbers
12 ga 7500-35280 made from 1907-1940
16 ga 300075-303875 made from 1912-1940

Savage model 1920 20/26
1000-5426 made in 1920
5427-5888 made in 1921
5889-7091 made in 1922
7092-8273 made in 1923
8274-9214 made in 1924
9215-9901 made in 1925
9902-13001 made in 1926 (model 20/26)
Only 8901 made.