Collin County Property Tax Protest Savings Calculator

See what a lower Collin CAD value would save, unit by unit, with Collin County's 2025 rates preloaded.

Short answer: savings = value reduction × your combined rate. In Plano (1.707713%), every $10,000 off your value saves about $170.77 a year.

Build your estimate

Rate source

Pick my taxing units

Enter a combined rate I already know

Taxing units

County

City

If you live outside any city limits, choose "Unincorporated / no city."

School district (ISD)

Search special districts

MUDs, ESDs, and similar districts depend on your exact address. None are selected by default — verify yours on your appraisal district's site.

Select a county first.

Property values

Noticed (appraised) value this year ($)

Target value after protest ($)

Support this with comparable sales or an unequal-appraisal comparison — see the prep checklist below.

Do you have a residence homestead exemption on this property?

Yes

Are you age 65+ or disabled?

Yes

Only affects the units-picker mode, where it adds the school homestead exemption automatically.

Per-unit savings
Taxing unit	Rate	Noticed tax	Target tax	Savings

Collin County example

$400,000 noticed → $360,000 target, homestead, pick Plano and Plano ISD, then tick Collin County Junior College District.

$5,375.48Tax at $400,000
$4,692.40Tax at $360,000
$683.09Yearly savings
1.707713%Combined rate

Appraisal district: Collin Central Appraisal District (Collin CAD)
Protest deadline: May 15 (next business day if that falls on a weekend), or 30 days after the notice is mailed — whichever is later (Tax Code §41.44). Check your notice.

Questions

How much could a protest save in Plano?

If a $400,000 Plano homestead is lowered to $360,000, the bill drops by about $683.09 a year: the $40,000 reduction × the combined 1.707713%.

How do I file a protest with Collin CAD?

Online through the Taxpayer Portal (onlineportal.collincad.org), using the Owner ID and eFile PIN printed in the top-right section of your mailed Appraisal Notice. By mail (postmarked by the deadline) or by hand / 24-hour drop box: 250 Eldorado Pkwy, McKinney TX 75069. Phone 469-742-9200. Collin CAD says the ARB does not accept protests by fax, email or helpdesk.

What is the Collin County protest deadline?

May 15 (next business day if that falls on a weekend), or 30 days after the notice is mailed — whichever is later (Tax Code §41.44). Your notice from Collin CAD shows the exact date.

Do I need to hire a protest company?

No. Filing is free and you can present your own evidence. The free Collin CAD protest kit walks you through it.