Tides Today & Tomorrow in Boston, MA

TIDE TIMES for Saturday, July 18, 2026
The tide is currently falling in Boston, MA.
Next low tide : in 20m at 9:18 pm (0.3 ft)
Next high tide (tomorrow) : 3:33 am (10.4 ft)
Sunset today : 8:17 pm
Sunrise tomorrow : 5:23 am
Moon phase : Waxing Crescent (23% illuminated)
Tide Station Location : Station #8443970
Common Questions About Tides

Boston, MA Tides - May 2078

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun2:289.83:088.58:540.69:021.85:387:43Waning Gibbous1Sun
2Mon3:099.63:538.49:380.89:482.05:367:44Waning Gibbous2Mon
3Tue3:559.54:428.310:270.910:392.15:357:46Third Quarter3Tue
4Wed4:479.45:368.311:201.011:362.05:347:47Third Quarter4Wed
5Thu5:449.46:318.612:160.95:327:48Third Quarter5Thu
6Fri6:449.67:279.112:351.71:110.75:317:49Third Quarter6Fri
7Sat7:459.88:229.71:351.22:070.45:307:50Waning Crescent7Sat
8Sun8:4510.19:1510.52:340.53:020.15:297:51Waning Crescent8Sun
9Mon9:4210.410:0611.23:32-0.23:54-0.35:287:52Waning Crescent9Mon
10Tue10:3710.710:5611.74:27-0.94:45-0.55:277:53New Moon10Tue
11Wed11:3010.811:4512.15:20-1.55:35-0.65:257:54New Moon11Wed
12Thu12:2410.86:12-1.76:25-0.55:247:55New Moon12Thu
13Fri12:3612.11:1810.57:04-1.77:16-0.25:237:56Waxing Crescent13Fri
14Sat1:2811.92:1210.27:56-1.58:080.25:227:57Waxing Crescent14Sat
15Sun2:2111.53:079.88:49-1.09:020.75:217:58Waxing Crescent15Sun
16Mon3:1610.94:059.49:45-0.49:591.25:208:00Waxing Crescent16Mon
17Tue4:1410.35:059.110:430.210:591.65:198:01First Quarter17Tue
18Wed5:169.76:068.911:430.75:188:02First Quarter18Wed
19Thu6:199.37:058.912:021.812:421.15:188:03First Quarter19Thu
20Fri7:219.08:019.01:051.81:381.35:178:03First Quarter20Fri
21Sat8:218.98:519.22:051.72:301.45:168:04Waxing Gibbous21Sat
22Sun9:158.99:369.53:011.53:181.55:158:05Waxing Gibbous22Sun
23Mon10:038.910:169.73:501.24:011.55:148:06Waxing Gibbous23Mon
24Tue10:468.910:549.94:340.94:411.55:148:07Waxing Gibbous24Tue
25Wed11:279.011:3010.05:140.75:191.55:138:08Full Moon25Wed
26Thu12:068.95:530.55:571.55:128:09Full Moon26Thu
27Fri12:0710.112:468.96:310.46:361.55:128:10Full Moon27Fri
28Sat12:4510.11:258.87:110.47:161.65:118:11Full Moon28Sat
29Sun1:2410.12:068.77:510.47:561.75:108:12Waning Gibbous29Sun
30Mon2:0410.12:478.78:320.48:391.75:108:12Waning Gibbous30Mon
31Tue2:4710.03:318.79:160.59:261.85:098:13Waning Gibbous31Tue
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8443970)

Common Questions About Boston, MA Tides

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What time does the tide turn (slack tide) in Boston, MA today?

Slack tide in Boston, MA is approximately 12:25 am — midway between the next high and low tide, when tidal current is weakest. This is the preferred window for boat crossings, underwater visibility, and fishing in areas with strong currents.

Is this week a spring tide or neap tide in Boston, MA?

Boston, MA is currently in a transitional phase. Tonight's moon is 23% illuminated. Spring tides (largest swings) occur near new and full moons; neap tides (smallest swings) occur near first and third quarter moons. Tidal ranges this week are shifting between spring and neap.

What datum are Boston, MA tide heights measured from?

Tide heights on this page are measured from Mean Lower Low Water (MLLW), the U.S. NOAA standard. A height of 0 ft represents the 19-year average of each day's lower low tide. Negative values indicate a "minus tide" — water levels below that long-term reference.

What factors can affect the tide predictions for Boston, MA?

Tide predictions for Boston, MA come from NOAA's harmonic analysis and are typically accurate within about ±10 minutes on timing and ±0.5 ft on height. Actual water levels can deviate further due to sustained winds, atmospheric pressure changes, river flow, and storm surge. During major weather events, be sure to check US Harbors weather pages for factors that could impact tidal predictions.

Which NOAA station provides tide data for Boston, MA?

Tide data for Boston, MA is sourced from NOAA Station #8443970. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8443970.

What is the moon phase in Boston, MA tonight?

Tonight the moon over Boston, MA is Waxing Crescent (23% illuminated). This places Boston, MA in a transitional tide cycle, so tidal ranges are shifting between spring and neap this week.

US Harbors Tidal Data

The data in our tide charts, tide tables, and tide graphs is provided by NOAA and others. These predictions are derived mathematically from numerous inputs, including data from historical tide stations and nearby locations where sensors are actively recording. As shown in the tide graph at the top of this page, “Predicted” tides (blue) are what forecasting models expect to happen. “Observed” tides (red) are those recorded by local sensors in real time, overlaid on the predictions for direct comparison. We display Observed water levels for a select group of harbors including Portland, Maine, where a physical sensor monitors water levels in real time.

LEARN MORE ABOUT OUR TIDE DATA