B737 flight crew reported receiving a new release with a weight increase after takeoff.

Attributes
ACN	1514784
Time
Date	201801
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Flight Plan	IFR
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Type 1013
Person 2
Function	First Officer
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine Flight Crew Instrument
Events
Anomaly	Deviation - Procedural Published Material / Policy Deviation - Procedural Weight And Balance

Narrative:

I had signed for release 1; and it was still current at push back. Weights were late and when they finally came I did not compare planned zero fuel wt from flight plan with finals; I just looked at the line where it indicates change in weight. I was taxing at an unfamiliar airport. It said final weight had only increased 40 lbs. After takeoff I realized that our final weight was actually about 3500 lbs more than release 1 planned weight. The dispatcher had issued release two with a higher zero fuel weight during our taxi out; but had not sent an ACARS message to tell us or sent the new plan to the printer. We did not know a new release was issued until enroute when I questioned it. Since the new flight plan had the actual zero fuel wt on it the final wts message didn't reflect the increase or tell us to contact dispatch like I would expect normally.

Original NASA ASRS Text

Title: B737 flight crew reported receiving a new release with a weight increase after takeoff.

Narrative: I had signed for release 1; and it was still current at push back. Weights were late and when they finally came I did not compare planned zero fuel wt from flight plan with finals; I just looked at the line where it indicates change in weight. I was taxing at an unfamiliar airport. It said final weight had only increased 40 lbs. After takeoff I realized that our final weight was actually about 3500 lbs more than release 1 planned weight. The dispatcher had issued release two with a higher zero fuel weight during our taxi out; but had not sent an ACARS message to tell us or sent the new plan to the printer. We did not know a new release was issued until enroute when I questioned it. Since the new flight plan had the actual zero fuel wt on it the final wts message didn't reflect the increase or tell us to contact dispatch like I would expect normally.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.