20150322181111_create_zipcodes.rb

class CreateZipcodes < ActiveRecord::Migration
  def change
    create_table(:zipcodes, id: false) do |t|
      t.integer :zipcode, primary_key: true
      t.string :city
      t.string :street
      t.string :company
      t.boolean :provins
      t.integer :country

      t.timestamps null: false
    end
  end
end

20150323181111_create_residences.rb

class CreateResidences < ActiveRecord::Migration
  def change
    create_table :residences do |t|
      t.string :name
      t.string :address
      t.belongs_to :zipcode, index: true

      t.timestamps null: false
    end
    add_foreign_key :residences, :zipcodes
  end
end

error

Mysql2::Error: Cannot add foreign key constraint: ALTER TABLE `residences` ADD CONSTRAINT `fk_rails_e76d45279d`
FOREIGN KEY (`zipcode_id`)
  REFERENCES `zipcodes` (`id`)

Try create_table :zipcodes do |t|
Without id: false

@completit it works now, it was the space after create_table (:zipcodes.... there made the mistake.