A process for preparing 3,6-dichloro-2-methoxybenzoic acid (DICAMBA), said process comprising: a. diazotizing 2,5-dichloroaniline with nitrosylsulfuric acid in at least one first fluid medium at a temperature in the range of 15 to 30 °C to obtain 2,5-dichlorophenyldiazonium salt; wherein the first fluid medium is selected from the group consisting of dichloromethane, 1,2-dichloroethane, chloroform, and carbon tetrachloride; b. hydroxylating the 2,5-dichlorophenyldiazonium salt by contacting the 2,5-dichlorophenyldiazonium salt with sulfuric acid at a temperature in the range of 150 °C to 170 °C to obtain 2,5-dichlorophenol and a residue comprising sulfuric acid, wherein the concentration of the sulfuric acid used for hydroxylating is in the range of 60 % to 75 % w/w, and wherein the residue comprising sulfuric acid is subjected to recovery of sulfuric acid; c. forming alkali metal 2,5-dichlorophenolate by reacting 2,5-dichlorophenol with an alkali metal hydroxide in at least one second fluid medium, wherein the moisture content of the alkali metal 2,5-dichlorophenolate is in the range of 0.005 to 0.05 % w/w; d. carboxylating the alkali metal 2,5-dichlorophenolate at a temperature in the range of 60 °C to 160 °C to obtain alkali metal salt of 3,6-dichlorosalicylic acid; e. methylating the alkali metal salt of 3,6-dichlorosalicylic acid, in at least one third fluid medium, with a methylating agent selected from the group consisting of methyl chloride (CH 3 Cl) and dimethyl sulfate ((CH 3) 2 SO 4) at a temperature in the range of 60 °C to 160 °C to obtain methyl 3,6-dichloro-2-methoxybenzoate (DICAMBA ester); and f. hydrolysing the DICAMBA ester at a temperature in the range of 50 °C to 130 °C to obtain DICAMBA; wherein the step of diazotizing involves slow addition of a solution of 2,5-dichloroaniline in the first fluid medium to nitrosylsulfuric acid, wherein the slow addition is carried out over a time period in the range of 5-50 hours by controlling the temperature of the reaction mixture, thereby preventing decomposition of the 2,5-dichlorophenyldiazonium salt. a. diazotizing 2,5-dichloroaniline with nitrosylsulfuric acid in at least one first fluid medium at a temperature in the range of 15 to 30 °C to obtain 2,5-dichlorophenyldiazonium salt; wherein the first fluid medium is selected from the group consisting of dichloromethane, 1,2-dichloroethane, chloroform, and carbon tetrachloride; b. hydroxylating the 2,5-dichlorophenyldiazonium salt by contacting the 2,5-dichlorophenyldiazonium salt with sulfuric acid at a temperature in the range of 150 °C to 170 °C to obtain 2,5-dichlorophenol and a residue comprising sulfuric acid, wherein the concentration of the sulfuric acid used for hydroxylating is in the range of 60 % to 75 % w/w, and wherein the residue comprising sulfuric acid is subjected to recovery of sulfuric acid; c. forming alkali metal 2,5-dichlorophenolate by reacting 2,5-dichlorophenol with an alkali metal hydroxide in at least one second fluid medium, wherein the moisture content of the alkali metal 2,5-dichlorophenolate is in the range of 0.005 to 0.05 % w/w; d. carboxylating the alkali metal 2,5-dichlorophenolate at a temperature in the range of 60 °C to 160 °C to obtain alkali metal salt of 3,6-dichlorosalicylic acid; e. methylating the alkali metal salt of 3,6-dichlorosalicylic acid, in at least one third fluid medium, with a methylating agent selected from the group consisting of methyl chloride (CH 3 Cl) and dimethyl sulfate ((CH 3) 2 SO 4) at a temperature in the range of 60 °C to 160 °C to obtain methyl 3,6-dichloro-2-methoxybenzoate (DICAMBA ester); and f. hydrolysing the DICAMBA ester at a temperature in the range of 50 °C to 130 °C to obtain DICAMBA;