Educational

How Address Verification APIs Are Priced (2026)

Q: What happens when I run out of lookups?

It depends on the model. Plan-plus-overage vendors bill each extra lookup. Prepaid block vendors such as Smarty stop answering with a 402 error until a new block is bought. Check this before launch, because a cutoff at checkout blocks orders.

Five pricing models, public prices at three volumes, and the costs that do not show up on the pricing page.

Stacey Dias

September 27, 2026 · 7 min read · Prices read September 27, 2026

Address verification APIs are priced per lookup, but vendors package that five different ways: pay per 1,000, prepaid blocks, a plan plus overage, credits, or free with another purchase. At 10,000 US lookups a month, public prices on September 27, 2026 ranged from $12 to $250. At 1 million a month, several vendors publish no price at all.

We are sthan.io, one of the vendors in the table. Every figure below comes from the vendor's own public pricing page, read on the date shown. Prices change, so check the source before you decide.

The five pricing models

Model	How it works	Examples	Watch for
Pay per 1,000	Metered, billed after use, often cheaper per unit at higher tiers	Google, Radar	No ceiling on the bill
Monthly tiers	A fixed monthly price for a set number of lookups	sthan.io	Rate limits per tier
Prepaid blocks	Buy a block of lookups, use it up	Smarty	Service stops when the block runs out
Plan plus overage	Monthly fee with lookups included, extra lookups billed	PostGrid, Lob	Overage rate, base fees
Credits	Buy credits, each lookup uses one or more	Melissa, Loqate	Credits per address, expiry
Bundled	Free with another purchase	EasyPost, with shipping labels	Only free if you buy the other thing

Public prices at 10K, 100K and 1M lookups a month

US address verification, monthly cost in US dollars. Where no plan matches the volume exactly, we show the cheapest listed option that covers it.

Vendor	Free	10K / month	100K / month	1M / month
sthan.io	100 / month	$12	$85 (150K plan)	$300
PostGrid	500 credits	$45	$475 (Growth $225 + overage)	$4,975 by overage math; Enterprise by quote
Google Address Validation Pro	5,000 / month	$85	$1,615	$12,155
Smarty (US Core)	1,000 once, 42-day trial	$88	$485 (170K plan)	Contact sales
Lob	Not stated	$250 (Startup $25 + overage)	$900 (Growth $450 + overage)	$9,000 by overage math; Enterprise by quote
Radar	None	From about $20	From about $200	From about $2,000
Melissa	1,000 credits / month after a $4.97 fee	Credit packs: $40 for 10K, $350 for 100K, $3,200 for 1M credits. The page states both 3 and 10 credits per US address, so the cost per address is unclear.
Loqate	Free trial	Verification listed as price on application
EasyPost	With label purchases	Standalone verification price not published

What stands out: at 10K a month the spread is about 20 times, from $12 to $250. At 1M a month, several vendors publish no price at all. Google gets expensive fast once past its free 5,000: its Enterprise SKU costs more again, $225 at 10K and $17,975 at 1M.

Costs that are not on the pricing page

Running out. Smarty has no overage: when a block runs out, the API returns a 402 error until a new block is bought. On a checkout form, that blocks orders.
Credits per address. With credit pricing, the price per credit is not the price per address. Ask how many credits one US lookup uses.
Expiry. Loqate credits are valid for 12 months after purchase. Unused credits are lost.
Base fees. Lob's verification plans sit next to its print plans, which start at $260 and $550 a month. Confirm whether they apply if you only verify.
Separate products. Autocomplete, parsing and geocoding are often priced separately from verification. At sthan.io, parsing is $8 for 10K, geocoding $5 for 10K and autocomplete $7 for 100K a month.
Rate limits. Lower tiers often cap requests per minute. Check the cap against your peak traffic, not your monthly total.
Wrong answers. The cheapest lookup is expensive if it silently returns the wrong address. See how to test an address API's accuracy.

Questions to ask before you buy

What does one US lookup cost at my real monthly volume, including overage?
What happens at the limit: overage, throttling, or a hard stop?
Do unused lookups or credits expire?
Is there a base or platform fee on top?
What is the request-per-minute cap on my tier?
Do I need CASS certification for my use? Often you do not. See do you need CASS certification.

Frequently Asked Questions

How much does an address verification API cost?

At 10,000 lookups a month, public prices on September 27, 2026 ranged from $12 (sthan.io) to $250 (Lob Startup with overage), with Smarty at $88, Google Address Validation Pro at $85 and PostGrid at $45.

What happens when I run out of lookups?

Plan-plus-overage vendors bill each extra lookup. Prepaid block vendors such as Smarty stop answering with a 402 error until a new block is bought. Check this before launch.

Is Google Address Validation cheaper because of the free tier?

Only at low volume. The Pro SKU includes 5,000 free events a month, then costs $17 per 1,000 up to 100,000. At 100,000 lookups a month that is $1,615.

Sources

All read September 27, 2026: sthan.io/pricing/united-states, smarty.com/pricing/us-address-verification, developers.google.com/maps/billing-and-pricing/pricing, postgrid.com/pricing-address-verification, melissa.com/pricing, loqate.com/en-us/pricing, lob.com/pricing/address-verification, easypost.com/address-verification-api, radar.com/pricing.

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Written by Stacey Dias

Stacey Dias writes about what address APIs cost at real volumes, pricing models, and side-by-side vendor comparisons.