There are two estimates circulating: $54 billion per year from Heritage and $116 billion per year from FAIR.

There are also fact checks stating that the estimate from FAIR either is mostly false, or fatally flawed (suggesting that FAIR’s estimate should be between $3.3 to $15.6 billion a year should they use “the correct numbers”).

Let’s take a look at the numbers and methodology, from estimates, fact checks and other sources.

1. Number of illegal immigrants

Heritage: 11.5 million (data from 2010) , FAIR: 12.5 million (published in 2017), Pew: 10.7 million (2016), Yale: 22.1 million — “95% probability range is 16 million to 29 million, with 22.1 million as the mean” (2018).

All the numbers are estimates, so there is no single “correct number”. Anybody who claims there is — makes a false statement.

2. How many children of illegal immigrants (US citizens) who is not in workforce?

Presumably age 0–16 years. They are eligible for benefits; not in workforce, hence don’t generate tax revenue.

FAIR: 4.2 million.

3. How many children of illegal immigrants (US citizens) who is a part of workforce?

Presumably age 16 and over. Eligible for benefits and part of them is working thus generating tax revenue.

FAIR: no estimate.

Critics use it as an excuse to reduce financial burden by the cost of education expenses towards illegal immigrants’ children, $31.7 billion annually.

Critics of FAIR estimates when talking about children of illegal immigrants use statements like “Workers with higher education earn more money and pay more in tax dollars.” without any numbers indicating which share of illegal immigrants children got higher education. Meanwhile Department of Education provides clear data to explain the environment where US-born children of illegal immigrants are growing in: Among undocumented youths ages 18–24, 40% have less than a high school education compared to 8% for U.S.-born counterparts (US Dept. of Education, 2015). So, not only critics allow themselves to use irrelevant statements, they use such statements to create a false impression that children of illegal immigrants are getting higher education as a norm.

With significantly less than average education in their families it’s hard to believe that the US citizens born to illegal immigrants overall will be having better education level than median Americans and earning more than median income, there is no evidence that they do. According to CATO, tax contribution from population with less than $50K/year income is negative, in other words, even after getting a job (keep in mind, some fraction of them will never work) most children from illegal immigrants will be a burden to society:

4. How much money spent on law enforcement against illegal immigrants?

FAIR includes all budget for border protection and law enforcement.

I tend to agree with critics that the US would protect the border with or without illegal immigrants present, so we can exclude it from the numbers. I don’t agree with final reduction number ($11.9 billion), in my opinion it should be $13.1 billion (total ) minus $6.0 billion (customs and border protection) to bring reduction number to $7.1 billion.

5. Welfare benefits — should we include children?

Yes, we should.

Critics state that we also should include tax generated by children later in life and they are correct, we should. It just happens, that tax generated later in life by children of illegal immigrants is most likely to be negative, as shown above.

6. What about Healthcare?

Critics claim that “Overall, all immigrants consume 55 percent less in healthcare dollars per capita than natives” without separating legal immigrants from illegal. Legal immigrants usually pay for insurance and therefore consume what they paid for, unlike illegals.

The study does not address contribution by legal / illegal immigrants, therefore cannot be used as an argument against numbers for illegal immigrants.

FAIR states $17.1 billion of federal medical expenditure, $12.1 state medical expenditure (total: $29.2 billion).

7. Conclusion

Even if we reduce FAIR estimate of financial burden by $7.1 billion, it would be still above $100 billion per year with assumption that we have 12.5 million of illegal immigrants. If number of illegal immigrants closer to conservative estimate of Yale study, 16.7 million, it would make the immediate burden even higher.

There is no compelling argument against this number. Critics speculate that children of illegal immigrants will generate positive tax contribution which would eventually offset all the welfare, expenditures and other cost they and their parents inflicted on society. There is no evidence that these children as a group will earn more than median income considering significantly lower education level in their families comparing to average Americans, therefore overall they will likely have less than median income which would have negative impact on society financials as shown above.