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Liberating Data from NYC Property Tax Bills – Chris Whong

Property Tax constitutes the single biggest source of revenue for the New York City Government, accounting for approximately $22.5 Billion dollars in the Modified FY2016 Budget. That’s a lot of money, and I’ve always been curious about how properties are assessed, how exemptions and abatements are applied, and what the overall property tax contribution is of a neighborhood, a block, or any other chunk of the city.

As it turns out, everything about property taxes is public record, but there isn’t really any quality bulk data around about it in NYC. Some aspects of property taxes show their face in PLUTO, including assessed value and abatement, but I learned a few years ago that that’s only part of the story, and you can’t infer from PLUTO how much a property actually pays in taxes. For that information, you have to look at the bills, which are also public record.

The NYC Department of Finance has an online tax bill lookup tool, where you can search for any property by BBL (Borough, Block, and Lot Numbers) or Address. Every statement and bill is available, going back for several years.

Let’s take a look at the bill for 1 Centre Street, a building owned by the city government. The bill for June 2015 is available as a PDF from this URL:

If you scroll down to the 2nd page, you’ll see a nicely formatted section calledAnnual Property Tax Detail, and hereis where you’ll find all of the goodies, including “the bottom line”, or how much that property owes the city for a given tax cycle.

You can see from the bill that if this building were not city-owned, its owner would have to fork over $7.4 Million a year. You can also see that this figure is based on the Billable Assessed Value of $69.8M times the tax rate of 10.6840% for commercial properties. The math is clear, but the source of the Billable Assessed value and the Estimated Market Value are not… but that’s another blog post. (It’s a dissertation, really… Here’s a great article from City&State that talks about several administrations’ failed attempts to reform the property tax system, and how two comparable properties can pay very different taxes based on how fast their neighborhoods appreciated in value. The most interesting tidbit is that renters are shouldering more property tax burden than homeowners, because of the way apartment buildings are taxed.)

Here’s another bill that shows exemptions ANDabatements together, saving this owner over $5,000 due to School Tax Relief (STAR) exemption and the Co-op/Condo Abatement:

Back in 2013, I put together a little project to extract these nuggets of data, as I wanted to make a simple web map that would allow you to explore property taxes. To accomplish this, we wrote a series of scripts to download thousands of tax bills and scrape the text out of them. The text was then parsed, resulting in machine-readable data for each property we had a bill for. We ended up pulling out most of the data for Manhattan (condos excluded), and the rudimentary map is still up today at (this hasn’t been updated since, and won’t be) It was always my intention to expand it to the rest of the city, and to share the bulk data, but like so many civic hacking projects, it never happened.

Last year, NYC Civic Hacker John Krauss locatedanother gold mineof data in the tax bills, specifically the number of rent stabilized units in an apartment building. Activists and renter’s rights groups had been in search of authoritative data on rent stabilized units, and John figured out that he could get high quality data at the buildinglevel by scraping every bill for apartment buildings with over 6 units. He found that surcharges for rent stabilization revealed a massive concentration of stabilized apartment loss in certain neighborhoods. Read his blog post about the rent stabilization data here, and check out the raw tax bills and data at There’s also a great article at ProPublica about the rent stabilization failure-to-report-but-still-getting-the-tax-break situation.

Ben Wellington (iQuantNY) has also done an analysis of the rent stabilization data that was liberated from the tax bills, showing the net change over time among other things. Read it here.

We teamed up to expand to include every BBL in the city, condominiums included, with a goal of assembling high-quality granular data including every exemption and abatement in the city. We used MapPLUTO 15v1 as our master list of BBLs, and the DOF assessment rolls to get an exhaustive list of condo BBLs and to join the condo units to their physical tax lot.

Here’s the Data

The data exist in two tables,one with a row for each BBL in the city, containing estimated market value, tax rate, total tax due, etc, and the other containing a row for each individual exemption and abatement found in the bills. There is a one-to-many relationship between these tables, as many exemptions and abatements can be associated with a single BBL. Million Rows

Columns: address – street address, collected from the bill bbl – 10-digit Borough, Block, and Lot ID ownername – owner name, pulled from the bill condo – ‘lot’ for condo lot BBLs, ‘unit’ for condo unit BBLs, empty for all others condonumber – corresponding condominium number for condo lot or unit taxclass – the tax class of theproperty taxrate – the tax rate associated with the tax class emv – estimated market value bav – billable assessed value tbea – tax before exemptions and abatements (bav x taxrate) tba – tax before abatements propertytax – total tax due (the bottom line)

june15exab.csv750K rows

Columns: bbl – 10-digit Borough, Block, & Lot ID that this exemption or abatement is associated with type – ‘exemption’ or ‘abatement’ detail – text of the exemption or abatement pulled from the bill amount – dollar amount of the exemption or abatement

These two tables were derived from the very large rawdata.csv on You can see the exact SQL queries and some other aspects of our methodology on the notes page.

A Few Good Queries

According to the data, the total tax before exemptions and abatements is $34.5 Billion. This is, in theory, the amount the city could collect if there were no exemptions and abatements. I’d love to see what this number would be if real market values were taken into account citywide.

The total tax due (the sum of all of the bottom lines in the bills) is $21.6 Billion,meaning the total amount of tax exemptions and abatements is $12.9 Billion. Of course, many of the exemptions are simply due to the land being owned by a government agency (does it make sense for a city government to pay itself tax? Should cities charge property tax to federal government-owned land in their jurisdictions?)

Let’s take a high-level look at the exemptions and abatements.

There are 147 unique exemption types. There are 42 exemption types with 10 or fewer occurrences. There are 7 with only 1 occurrence: indust waste facility, prof. maj lea sports, nys med care fac fin, patrol salvage, solar/wind energy, state retire system, ltd profit hsng co:l (Someone map these please! Ok, I’ll do it myself, give me a few days)

You can see the full list of all 147 exemptions along with a sum ($) and count column in the table below. I’ll keep my opinions to myself for now and just show you the data.

detail sum count park $-1,235,613,825 4242 dept. of education $-962,818,626 1276 port auth-air termin $-913,424,673 39 fed govt land bldgs $-566,423,433 121 icip $-512,009,171 6427 house of worship $-476,243,408 5829 nyc housing auth $-427,602,366 1121 hospital $-423,899,214 478 421a (20 yr not cap $-334,361,000 291 dept real est (dcas) $-326,204,300 2317 college-university $-306,038,884 298 421a (15 yr not cap) $-279,189,007 33571 nyc industrial dev $-254,687,155 392 421a (25 yr not cap $-252,078,327 19785 battery park auth $-238,561,043 3076 new mult dwellings – 421a $-225,805,259 15956 nys urban dev (esdc) $-223,169,276 265 dormitory authority $-196,179,285 156 state lands bldgs $-188,206,157 702 health & hospitals c $-187,499,525 53 dept small bus svcs $-185,986,785 189 j-51 alteration $-176,986,092 22283 edc – pilot $-154,825,087 62 port auth-world trad $-144,282,806 4 bd higher ed (cuny) $-144,110,833 121 420c housing $-137,270,998 1487 religious-school $-136,316,447 625 basic star – school tax relief $-131,481,459 321063 charitable $-122,001,696 1369 senior citizens homeowners exemption $-118,970,134 44436 school-elem,hs,acad $-97,272,864 278 mta-nyc transit $-82,620,953 237 dept pub work (dep) $-76,593,333 856 post office $-76,529,620 123 roosevelt island $-70,090,358 588 cemetery (private) $-69,699,532 191 student dormitory $-62,707,580 209 enhanced star – school tax relief $-62,542,225 82913 dept of correction $-60,485,450 7 hospital staff hsg $-60,265,761 403 faculty student hsg $-54,279,562 348 dept of sanitation $-53,215,234 133 public museum $-50,161,235 25 house pres devl adm $-49,520,011 1516 spec init pgm (sip) $-49,093,441 774 public library $-46,087,925 191 dept of traffic $-43,088,377 520 nyc educ const fund $-41,645,783 26 421a (15 yr cap) $-40,592,345 3546 prof. maj lea sports $-40,234,090 1 nfp-contemplated use $-37,451,904 298 fed hospital $-37,039,566 5 police dept $-36,494,205 198 dept of soc svc (hra $-36,451,518 110 foreign mission $-36,108,239 185 united nations $-35,967,692 10 nursing home $-35,626,822 76 mental-moral improve $-35,484,703 289 resid-conv. low manh $-29,054,091 2555 museum $-28,863,040 59 div of alt mgmt prog $-28,557,598 1003 cooper union $-28,356,603 4 chartble philan $-27,435,310 221 opera house $-26,254,281 4 school construc auth $-26,065,448 45 state aided pub hsg $-25,844,064 25 nyc hous auth-duplic $-25,801,287 99 perf arts bldg $-25,471,471 11 armed forces $-24,736,209 5 health center $-24,220,909 117 state hospital $-23,834,609 31 urban dev. act proj. $-23,677,638 9156 urban renewal $-21,201,190 120 dept water resources $-19,665,961 191 port auth-bus facilt $-19,318,732 5 charitable housing $-19,306,166 356 parsonage $-19,213,798 1059 fire dept $-18,638,363 258 benevolent $-18,069,075 144 port auth-indust dev $-16,820,008 50 state public works $-16,785,619 117 veteran exemption $-15,836,961 32132 st assisted priv hsg $-15,079,766 18 trust for cult rsrce $-14,637,483 250 ida – pilot $-13,208,444 48 foreign consulate $-13,102,555 102 academy of music $-12,826,211 9 police fire $-12,256,973 12 un development corp $-12,161,474 6 religious-dormitory $-11,549,266 52 mta – bridge&tunnel $-11,522,684 54 disabled homeowner $-11,221,103 4866 mta-lirr/metro north $-11,137,726 66 state retire system $-9,863,649 1 dept of health $-9,684,507 42 mitchell-lama (srt) $-9,301,681 81 military $-8,269,903 7 hsg dev fund co (srt $-7,919,965 30 dwelling from fed $-7,253,378 25 salvation army $-6,095,291 41 veteran portion fully exempt $-5,557,900 10708 veteran portion partially exempt $-5,470,235 10708 foreign embassies $-5,459,566 49 port auth-bridge/tun $-4,552,957 39 non-profit med dent $-3,849,513 3 dept of highways $-3,013,486 37 421a (10 yr cap) $-2,972,734 302 foreign staff hsing $-2,767,134 85 literary $-2,648,013 9 armory $-2,520,941 6 fraternal organiz $-2,236,242 5 redevelopment (srt) $-2,156,074 16 nys hous fin agency $-2,005,203 194 hip center $-1,898,830 10 nyc econ dev corp $-1,688,007 8 library $-1,589,163 13 historical $-1,463,651 21 421b (1-2 family) $-1,276,105 1384 religious missions $-1,085,091 29 a.l.,vfw,cwv,jwv,etc $-1,058,591 65 inst of arts sci $-895,239 5 theatrical corp $-839,432 9 public playground $-612,755 4 scientific $-539,996 9 borough president $-474,973 9 ltd profit hsng co:l $-423,894 1 clergy $-382,094 1331 cemetery (federal $-265,304 2 enf/law/child/animal $-259,496 3 bible $-245,976 2 vol. fire co. $-228,916 13 memorial assn $-211,529 6 amtrak (fed subsi rr $-151,217 3 ny state power auth $-137,642 3 limited div (srt) $-97,860 3 supvd. sportsmanship $-67,238 2 patrol salvage $-60,998 1 nys med care fac fin $-45,953 1 ser disabled veteran $-24,351 4 crime victims $-21,381 6 solar/wind energy $-12,379 1 indust waste facil $-10,150 1 lighthouse $-9,646 3 environ prot ex $-8,441 2 port auth – invalid $-910 3 fallout shelter $-153 2 veteran exemption total $126,567,562 10708

Something wonky is going on with that last line “veterans exemption total”. If anyone figures it out, please let me know.

Now the abatements, of which there are 9 distinct types:

detail sum count co-op/condo abatement $-419,578,051 41111 j51 abatement $-85,370,163 33884 residential conversion abatement $-39,932,014 2564 industrial & commercial abate prog $-28,433,537 429 lease abatement $-17,322,212 218 brooklyn bridge park pilot $-4,896,130 600 solar elec generating system abate $-4,643,480 2179 mitchell lama star benefit $-4,550,181 135 icip abatement $-1,180,589 84


By joining the data with MapPLUTO in CartoDB, we can visualize the tax footprint of the entire city. (Once joined, you can also use the rich lot-level data in PLUTO to analyze property taxes based on zoning, land use, etc) I have colored lots with zero tax due as pink, but bear in mind that it’s often not so simple and things like Payments in Lieu of Taxes (PILOTs) are not reflected in the tax bills. Condo units are outlined in yellow.

So there you have it… we turned 1.1 million pdfs into a high quality open dataset on NYC property taxes, including all exemptions and abatements. Data scientists everywhere, go forth and crunch the numbers, and please share your findings on twitter with me (@chris_whong), John Krauss (@recessionporn) and Ben Wellington (@iquantny). We can’t wait to see what you come up with!

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