The three grounds, verbatim from the regulation, because the differences matter.
The second branch of the third ground is deliberately narrow and reads that way: compromise "will be justified only where, due to exceptional circumstances, collection of the full liability would undermine public confidence that the tax laws are being administered in a fair and equitable manner", and the applicant is "expected to demonstrate circumstances that justify compromise even though a similarly situated taxpayer may have paid his liability in full." A further limb bars any effective-tax-administration compromise that "would undermine compliance by taxpayers with the tax laws." Compressing that into "the IRS can also settle if it seems unfair" overstates a door the regulation kept almost shut.
"Ability to pay, income, expenses, asset equity" is not the list of grounds, and this is the commonest error on the subject. Those four are what the IRS's own page says it considers, and they are the collectibility analysis. A page or a preparer who presents them as the grounds has quietly erased doubt as to liability and effective tax administration, which are the two routes available to someone who can pay but should not have to.
How the number is built. The IRS says it "generally approve[s] an offer in compromise when the amount you offer represents the most we can expect to collect within a reasonable period of time." In practice that is the equity in the taxpayer's assets plus a multiple of monthly income remaining after allowable expenses, computed on Form 433-A (OIC), Collection Information Statement for Wage Earners and Self-Employed Individuals, or Form 433-B (OIC) for a business. Section 7122(d)(2) requires the Secretary to publish national and local allowances for basic living expenses and, importantly, forbids using those schedules "to the extent such use would result in the taxpayer not having adequate means to provide for basic living expenses." An offer below what that arithmetic produces is unlikely to succeed; the statute does add, at 7122(d)(3)(A), that an offer from a low-income taxpayer may not be rejected "solely on the basis of the amount of the offer."
A doubt-as-to-liability offer is a different animal, and cheaper. The regulation provides that taxpayers submitting offers "solely on the basis of doubt as to liability will not be required to provide financial statements", and section 7122(d)(3)(B)(ii) requires the same thing at statute level for an offer relating only to liability. 26 CFR 300.3(b)(1)(i) charges no fee at all for such an offer. So the financial disclosure and the application fee that dominate discussion of this program both belong to the collectibility route, and someone who genuinely disputes the tax rather than their ability to pay it is on a separate and lighter track.
The fee, and its two waivers. The application fee is $205, set by 26 CFR 300.3(b)(1) and confirmed on Form 656 and on the IRS's own page. It is regulatory rather than inflation-adjusted, so it changes only when Treasury amends the regulation, which it last did in 2020. It is waived where the offer rests solely on doubt as to liability, and separately under section 7122(c)(3) for an individual whose adjusted gross income "does not exceed 250 percent of the applicable poverty level". Form 656-B carries the resulting table by household size and geography; the base figure for a one-person household in the 48 contiguous states is $15,960, and the certification threshold is two and a half times the guideline for the applicant's household size. A low-income applicant sends no fee, no down payment, and makes no monthly payments while the offer is under review.
The down payment, and where the money goes. Section 7122(c)(1)(A) requires 20 percent of the offered amount with a lump-sum offer, and defines a lump-sum offer as "any offer of payments made in 5 or fewer installments". A periodic payment offer instead arrives with the first proposed installment and continues monthly while the IRS evaluates it, and missing one of those (other than the first) "may be treated by the Secretary as a withdrawal". None of it is refundable: payments and the fee are applied to the liability, though section 7122(c)(2)(A) lets the taxpayer specify which year and which debt they go against.
The two-year rule is keyed to "not rejected", not to "no answer". Section 7122(f) provides that an offer "shall be deemed to be accepted by the Secretary if such offer is not rejected by the Secretary before the date which is 24 months after the date of the submission of such offer", excluding any period the liability is in dispute in a judicial proceeding. The IRS paraphrases this on its own page as automatic acceptance if it "doesn't make a determination within two years", which is looser than the statute; a withdrawal or a return of the offer as unprocessable is not a rejection, and the statutory wording is the one to rely on.
What acceptance actually costs, beyond the money. The offer terms in Section 7 of Form 656 are contractual, and three of them surprise people. The taxpayer agrees to "strictly comply with all provisions of the internal revenue laws, including requirements to timely file tax returns and timely pay taxes for the five year period beginning with the date of acceptance"; agrees that during those five years they "cannot request an installment agreement for unpaid taxes incurred before or after the accepted offer"; and gives up the right to challenge the settled debt in court or by refund claim afterwards, "even if the IRS defaults or rescinds the offer." Refunds for the year of acceptance are kept by the IRS, and a federal tax lien is not released until the offer terms are satisfied.
The honest numbers, and the industry built on their absence. In fiscal year 2025 taxpayers submitted 38,797 offers and the IRS accepted 5,464, per the IRS Data Book's delinquent collection activities table. Offers submitted and offers accepted in a single year are not the same cases, so that is an approximation rather than a true cohort acceptance rate, but the order of magnitude is roughly one in seven and it has been in that region for years. Advertising promising to settle tax debts "for pennies on the dollar" is selling a program whose arithmetic is driven mainly by the taxpayer's own assets and income. A representative can affect how expenses and asset values are characterized, and can spot a ground the taxpayer had not considered, which is real work; what nobody can do is move the balance sheet the offer is computed from. The IRS's own caution on the point is unusually direct: "Explore all other payment options before you submit an offer in compromise. The Offer in Compromise Program is not for everyone. Be sure to check the qualifications of any tax professional you hire to help you file an offer."