With Geocodio, you can match addresses or coordinates to the Census Bureau's American Community Survey data for average income levels. You can append it to your data by selecting "economics" in Step 4 of the upload process.
This data is not for the individual household. It is for the Census Block.
This data is provided at the Census Block Group level and is available from the five-year American Community Survey, last published in 2015. (The 1-year American Community Surveys do not have granularity at this level.)
We provide the data exactly as it is packaged by the Census Bureau in the breakouts it gives. The only change we have made is to add a "percentage" calculation to aid ease of use.
The data returned includes the following data points. For each data point, the data returned includes the value, margin of error, and percentage.
Household income (Table #B19001)