The filter thread size of Tamron AF 18-270mm F3.5-6.3 Di II VC LD Aspherical IF MACRO is 72mm.
Below are links to the filters that we recommend you to consider for your Tamron AF 18-270mm f3.5-6.3 II VC LD:
Read our detailed Tamron AF 18-270mm F3.5-6.3 Di II VC LD Aspherical IF MACRO Review