Is there a different allowance for seniors ?

[macuser_22]

If you mean standard deduction - then yes.

2019 standard deductions

$12,200 Single
$18,350 Head of Household
$24,400 Married Jointly

Add an additional $1,300 for over age 65 or blind
This amount increases to $1,650 if the taxpayer is also unmarried.

[Critter]

Do you mean the standard deduction ?  

Standard Deduction Amounts for the 2019 Tax Year 

Filing Status	Deduction Amount
Single	$12,200
Head of Household	$18,350
Married Filing Jointly	$24,400
Married Filing Separately	$12,200
Qualifying Widow(er)	$24,400

The Standard Deduction Based on Age or Blindness

Taxpayers who are age 65 and older and individuals who are legally blind receive an additional standard deduction. It's calculated by adding the taxpayer's standard deduction based on their filing status, plus an additional amount.

The additional amount for people who are blind or 65 and older is $1,300 each for married taxpayers, or $1,600 for unmarried taxpayers and head-of-household filers as of the 2019 tax year.