diff --git a/app/validators/poll_validator.rb b/app/validators/poll_validator.rb
index fd497c8d0..9d7321cad 100644
--- a/app/validators/poll_validator.rb
+++ b/app/validators/poll_validator.rb
@@ -14,6 +14,6 @@ class PollValidator < ActiveModel::Validator
     poll.errors.add(:options, I18n.t('polls.errors.over_character_limit', max: MAX_OPTION_CHARS)) if poll.options.any? { |option| option.mb_chars.grapheme_length > MAX_OPTION_CHARS }
     poll.errors.add(:options, I18n.t('polls.errors.duplicate_options')) unless poll.options.uniq.size == poll.options.size
     poll.errors.add(:expires_at, I18n.t('polls.errors.duration_too_long')) if poll.expires_at.nil? || poll.expires_at - current_time > MAX_EXPIRATION
-    poll.errors.add(:expires_at, I18n.t('polls.errors.duration_too_short')) if poll.expires_at.present? && poll.expires_at - current_time < MIN_EXPIRATION
+    poll.errors.add(:expires_at, I18n.t('polls.errors.duration_too_short')) if poll.expires_at.present? && (poll.expires_at - current_time).ceil < MIN_EXPIRATION
   end
 end
diff --git a/spec/validators/poll_validator_spec.rb b/spec/validators/poll_validator_spec.rb
new file mode 100644
index 000000000..941b83401
--- /dev/null
+++ b/spec/validators/poll_validator_spec.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe PollValidator, type: :validator do
+  describe '#validate' do
+    before do
+      validator.validate(poll)
+    end
+
+    let(:validator) { described_class.new }
+    let(:poll) { double(options: options, expires_at: expires_at, errors: errors) }
+    let(:errors) { double(add: nil) }
+    let(:options) { %w(foo bar) }
+    let(:expires_at) { 1.day.from_now }
+
+    it 'have no errors' do
+      expect(errors).not_to have_received(:add)
+    end
+
+    context 'expires just 5 min ago' do
+      let(:expires_at) { 5.minutes.from_now }
+      it 'not calls errors add' do
+        expect(errors).not_to have_received(:add)
+      end
+    end
+  end
+end