Sequelize How compare year of a date in query

TABLEA.findAll({
  where: sequelize.where(sequelize.fn('YEAR', sequelize.col('dateField')), 2016)
 });

You have to use .where here, because the lefthand side of the expression (the key) is an object, so it cannot be used in the regular POJO style as an object key.

If you want to combine it with other conditions you could do:

TABLEA.findAll({
  where: {
    $and: [
      sequelize.where(sequelize.fn('YEAR', sequelize.col('dateField')), 2016),
      { foo: 'bar' }
    ]
  }
 });

https://sequelize.org/v3/docs/querying/#operators