Note: Dial ‘0’ or +91 before the given STD code
| City | Area/Town | STD Code |
| SILCHAR | HAILAKANDI | 3844 |
| SILCHAR | KARIMGANJ | 3843 |
| SILCHAR | SILCHAR | 3842 |
| SILCHAR | VDARBONDH | 3841 |
| JORHAT | BOKAKHAT | 3776 |
| JORHAT | MAJULI | 3775 |
| JORHAT | GOLAGHAT | 3774 |
| JORHAT | SIBSAGAR | 3772 |
| JORHAT | MARIANI | 3771 |
| TINSUKIA (DIBRUGARH) | BIHUPURIA | 3759 |
| TINSUKIA (DIBRUGARH) | DHAKUAKHANA | 3758 |
| TINSUKIA (DIBRUGARH) | SADIYA | 3756 |
| TINSUKIA (DIBRUGARH) | MORANHAT | 3754 |
| TINSUKIA (DIBRUGARH) | DHEMAJI | 3753 |
| TINSUKIA (DIBRUGARH) | NORTH LAKHIMPUR | 3752 |
| TINSUKIA (DIBRUGARH) | DIGBOI | 3751 |
| TEZPUR | GOHPUR | 3715 |
| TEZPUR | RANGAPARA | 3714 |
| TEZPUR | MANGALDOI | 3713 |
| TEZPUR | TEZPUR | 3712 |
| TEZPUR | UDALGURI | 3711 |
| NAGAON | MORIGAON | 3678 |
| NAGAON | BAITHALANGSHU | 3677 |
| NAGAON | HOWRAGHAT | 3676 |
| NAGAON | BOKAJAN | 3675 |
| NAGAON | HOJAI | 3674 |
| NAGAON | HAFLONG | 3673 |
| NAGAON | NAGAON | 3672 |
| NAGAON | DIPHU | 3671 |
| NAGAON | MAIBONG | 3670 |
| BONGAIGAON (KOKRAJHAR) | ABHAYAPURI | 3669 |
| BONGAIGAON (KOKRAJHAR) | BIJNI | 3668 |
| BONGAIGAON (KOKRAJHAR) | BILASIPARA | 3667 |
| GUWAHATI | BARPETA ROAD | 3666 |
| GUWAHATI | TARABARIHAT | 3665 |
| GUWAHATI | HAJO | 3664 |
| BONGAIGAON (KOKRAJHAR) | GOALPARA | 3663 |
| BONGAIGAON (KOKRAJHAR) | DHUBRI | 3662 |
| BONGAIGAON (KOKRAJHAR) | KOKRAJHAR | 3661 |
| GUWAHATI | NALBARI | 3624 |
| GUWAHATI | BARAMA | 3623 |
| GUWAHATI | BOKO | 3621 |
| JORHAT | JORHAT | 376 |
| TINSUKIA (DIBRUGARH) | TINSUKHIA | 374 |
| TINSUKIA (DIBRUGARH) | DIBRUGARH | 373 |
| GUWAHATI | GUWAHATI | 361 |